diff --git a/daemon/codec.c b/daemon/codec.c
index 68fd50e71..ff34d066b 100644
--- a/daemon/codec.c
+++ b/daemon/codec.c
@@ -4061,6 +4061,8 @@ static void __dtx_send_later(struct codec_timer *ct) {
 	rwlock_lock_r(&call->master_lock);
 	__ssrc_lock_both(&mp_copy);
 
+	mp_copy.dtx = true;
+
 	if (dtxp) {
 		ilogs(dtx, LOG_DEBUG, "Decoding DTX-buffered RTP packet (TS %lu) now; "
 				"%i packets left in queue", ts, p_left);
@@ -4100,8 +4102,6 @@ static void __dtx_send_later(struct codec_timer *ct) {
 			mutex_unlock(&dtxb->lock);
 		}
 	}
-	if (ch && ch->encoder && mp_copy.ssrc_out)
-		mp_copy.ssrc_out->ts_out = ch->encoder->next_pts + ch->csch.first_ts;
 
 	mutex_lock(&dtxb->lock);
 
@@ -4726,6 +4726,15 @@ static void packet_encoded_tx(struct codec_ssrc_handler *ch, struct media_packet
 		if (!repeats)
 			break;
 	} while (repeats--);
+
+	// Save the clock of the actual output encoder for DTX restarts. The DTX decoder
+	// may run at a different rate and cannot supply the timestamp for this listener.
+	// Ordinary transcoding must retain the input timestamp origin when reconfigured.
+	if (mp->dtx && !is_dtmf) {
+		mp->ssrc_out->ts_out = ch->csch.first_ts + fraction_divl(pts + duration, cr_fact);
+		mp->ssrc_out->ts_out_time = rtpe_now
+				+ fraction_divl(duration, cr_fact) * 1000000LL / ch->handler->dest_pt.clock_rate;
+	}
 }
 
 
@@ -4923,8 +4932,14 @@ static tc_code packet_decode(struct codec_ssrc_handler *ch, struct codec_ssrc_ha
 {
 	tc_code ret = TCC_OK;
 
-	if (!ch->csch.first_ts)
+	if (!ch->csch.first_ts) {
 		ch->csch.first_ts = mp->ssrc_out->ts_out ?: packet->ts;
+		// A stopped encoder does not produce samples while prompts or floor
+		// blocking are active. Keep that elapsed time in the listener's RTP clock.
+		if (mp->ssrc_out->ts_out_time && rtpe_now > mp->ssrc_out->ts_out_time)
+			ch->csch.first_ts += (rtpe_now - mp->ssrc_out->ts_out_time)
+					* ch->handler->dest_pt.clock_rate / 1000000;
+	}
 
 	if (ch->decoder && ch->decoder->def->dtmf) {
 		if (packet_dtmf_event(ch, input_ch, packet, mp) == -1)
diff --git a/include/media_socket.h b/include/media_socket.h
index 7817118b5..f7fd7c716 100644
--- a/include/media_socket.h
+++ b/include/media_socket.h
@@ -313,6 +313,7 @@ struct media_packet {
 	struct sink_handler sink;
 	struct media_player_cache_entry *cache_entry;
 	bool recording_egress;
+	bool dtx; // processed by the DTX timer; retain the output encoder clock
 
 	struct rtp_header *rtp;
 	struct rtcp_packet *rtcp;
diff --git a/include/ssrc.h b/include/ssrc.h
index 66087ba1b..6094a9739 100644
--- a/include/ssrc.h
+++ b/include/ssrc.h
@@ -53,6 +53,7 @@ struct ssrc_entry_call {
 	uint32_t ssrc_map_out;
 	uint16_t seq_out;
 	unsigned long ts_out;
+	int64_t ts_out_time; // wall clock corresponding to the next output RTP timestamp
 	bool seq_set;
 
 	// RTCP stats
diff --git a/t/Makefile b/t/Makefile
index db85b9593..feb2e9cdc 100644
--- a/t/Makefile
+++ b/t/Makefile
@@ -90,7 +90,7 @@ include ../lib/common.Makefile
 	daemon-tests-bundle daemon-tests-dtls daemon-tests-rollback \
 	daemon-tests-rollback-redis daemon-tests-redis-srtp-index \
 	daemon-tests-recording daemon-tests-create daemon-tests-created-subscriptions daemon-tests-alias \
-	daemon-tests-kernel-api \
+	daemon-tests-kernel-api daemon-tests-dtx-clock \
 	daemon-tests-video daemon-tests-inject daemon-tests-dtx-dtmf
 
 TESTS := test-bitstr aes-crypt aead-aes-crypt test-const_str_hash.strhash
@@ -143,7 +143,7 @@ daemon-tests: daemon-tests-main daemon-tests-jb daemon-tests-pubsub daemon-tests
 	daemon-tests-bundle daemon-tests-dtls daemon-tests-rollback daemon-tests-rollback-redis \
 	daemon-tests-redis-srtp-index \
 	daemon-tests-recording daemon-tests-create daemon-tests-created-subscriptions \
-	daemon-tests-dtx daemon-tests-dtx-cn daemon-tests-dtx-no-shift daemon-tests-dtx-dtmf \
+	daemon-tests-dtx daemon-tests-dtx-cn daemon-tests-dtx-no-shift daemon-tests-dtx-dtmf daemon-tests-dtx-clock \
 	daemon-tests-alias \
 	daemon-tests-kernel-api \
 	daemon-tests-video daemon-tests-inject
@@ -184,6 +184,9 @@ daemon-tests-dtx:	daemon-test-deps
 daemon-tests-dtx-dtmf:	daemon-test-deps
 	./auto-test-helper "$@" perl -I../perl auto-daemon-tests-dtx-dtmf.pl
 
+daemon-tests-dtx-clock:	daemon-test-deps
+	./auto-test-helper "$@" perl -I../perl auto-daemon-tests-dtx-clock.pl
+
 daemon-tests-dtx-no-shift:	daemon-test-deps
 	./auto-test-helper "$@" perl -I../perl auto-daemon-tests-dtx-no-shift.pl
 
diff --git a/t/auto-daemon-tests-dtx-clock.pl b/t/auto-daemon-tests-dtx-clock.pl
new file mode 100644
index 000000000..fef1cc9a4
--- /dev/null
+++ b/t/auto-daemon-tests-dtx-clock.pl
@@ -0,0 +1,129 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+use NGCP::Rtpengine::Test;
+use NGCP::Rtpclient::SRTP;
+use NGCP::Rtpengine::AutoTest;
+use Test::More;
+
+# Repeated floor bursts must retain each output encoder clock through prompt playback.
+autotest_start(qw(--config-file=none -t -1 -i 203.0.113.1
+	-n 2223 -f -L 7 -E --silence-detect=1 --dtx-delay=50 --max-dtx=1)) or die;
+
+use Time::HiRes qw(time sleep);
+use IO::Select;
+
+# Exercise equal rates, different RTP rates, and the G.722 sample/RTP rate factor.
+for my $profile (
+	['PCMA/8000', 8, 8000, 100000],
+	['opus/48000/2', 96, 48000, 100000],
+	['G722/8000', 9, 8000, 0xfffff000],
+) {
+	my ($codec, $pt, $rate, $origin) = @$profile;
+	my $offer_pts = $pt == 96 ? '96 97' : $pt;
+	my $offer_attrs = "a=rtpmap:$pt $codec";
+	if ($pt == 96) {
+		$offer_attrs .= "\na=fmtp:96 useinbandfec=1\na=rtpmap:97 telephone-event/48000\na=fmtp:97 0-15";
+	}
+	my ($sock_a, $sock_b) = new_call([qw(198.51.100.10 5000)], [qw(198.51.100.10 5002)]);
+	my $name = "DTX output clock across playback: $codec";
+
+	my ($port_a) = offer($name, { codec => { transcode => [$codec] } }, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.10
+s=tester
+t=0 0
+m=audio 5000 RTP/AVP 0 101
+c=IN IP4 198.51.100.10
+a=rtpmap:101 telephone-event/8000
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.10
+s=tester
+t=0 0
+m=audio PORT RTP/AVP 0 $offer_pts 101
+c=IN IP4 203.0.113.1
+a=rtpmap:0 PCMU/8000
+$offer_attrs
+a=rtpmap:101 telephone-event/8000
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+	my ($port_b) = answer($name, {}, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.10
+s=tester
+t=0 0
+m=audio 5002 RTP/AVP $pt 101
+a=rtpmap:$pt $codec
+c=IN IP4 198.51.100.10
+a=rtpmap:101 telephone-event/8000
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.10
+s=tester
+t=0 0
+m=audio PORT RTP/AVP 0 101
+c=IN IP4 203.0.113.1
+a=rtpmap:0 PCMU/8000
+a=rtpmap:101 telephone-event/8000
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+
+	# A short prompt on its own SSRC interrupts the transcoder between bursts.
+	my $pcm = "\0" x 1600;
+	my $wav = pack('a4Va4a4VvvVVvva4V', 'RIFF', 36 + length($pcm), 'WAVE',
+			'fmt ', 16, 1, 1, 8000, 16000, 2, 16, 'data', length($pcm)) . $pcm;
+	my ($seq, $last_ts, $last_time, $audio_ssrc) = (100, undef, undef, undef);
+	for my $burst (0..2) {
+		for my $i (0..9) {
+			snd($sock_a, $port_b, rtp(0, $seq++, $origin + $burst * 16000 + $i * 160,
+					0x5678, "\x40" x 160));
+			sleep(0.02);
+		}
+		my $sel = IO::Select->new($sock_b);
+		my $end = time() + 0.3;
+		my $received = 0;
+		while (time() < $end && $sel->can_read(0.1)) {
+			my $p;
+			$sock_b->recv($p, 65535);
+			my ($out_pt, $q, $ts, $ssrc) = unpack('x C n N N', $p);
+			is($out_pt & 0x7f, $pt, 'burst uses the negotiated output codec');
+			$audio_ssrc //= $ssrc;
+			is($ssrc, $audio_ssrc, 'speech SSRC survives playback transitions');
+			my $now = time();
+			if (defined $last_ts) {
+				my $delta = ($ts - $last_ts) & 0xffffffff;
+				cmp_ok($delta, '<', 0x80000000, 'output clock does not rewind');
+				if ($now - $last_time > 1) {
+					# Receive after sending a 200 ms batch; allow that batching skew.
+					cmp_ok(abs($delta / $rate - ($now - $last_time)), '<', 0.3,
+							'RTP clock includes elapsed playback and silence');
+				}
+			}
+			$last_ts = $ts;
+			$last_time = $now;
+			$received++;
+		}
+		cmp_ok($received, '>=', 10, 'each burst produces output promptly');
+		rtpe_req('block media', $name, {'from-tag' => ft(), flags => ['directional']});
+		rtpe_req('play media', $name, {'from-tag' => tt(), blob => $wav});
+		sleep(0.2);
+		rtpe_req('stop media', $name, {'from-tag' => tt()});
+		while ($sel->can_read(0.01)) {
+			my $p;
+			$sock_b->recv($p, 65535);
+		}
+		sleep(1.4);
+		rtpe_req('unblock media', $name, {'from-tag' => ft(), flags => ['directional']});
+	}
+	rtpe_req('delete', $name, {'from-tag' => ft()});
+}
+
+done_testing();
diff --git a/t/auto-daemon-tests-dtx.pl b/t/auto-daemon-tests-dtx.pl
index e25e5e82e..c34982d37 100755
--- a/t/auto-daemon-tests-dtx.pl
+++ b/t/auto-daemon-tests-dtx.pl
@@ -22,7 +22,7 @@
 my ($sock_a, $sock_b, $sock_c, $sock_d, $port_a, $port_b, $ssrc, $ssrc_b, $resp,
 	$sock_ax, $sock_bx, $port_ax, $port_bx,
 	$srtp_ctx_a, $srtp_ctx_b, $srtp_ctx_a_rev, $srtp_ctx_b_rev,
-	@ret1, @ret2, @ret3, @ret4, $srtp_key_a, $srtp_key_b, $ts, $seq);
+	@ret1, @ret2, @ret3, @ret4, $srtp_key_a, $srtp_key_b, $ts, $seq, $resume_time);
 
 
 
@@ -705,10 +705,13 @@
 rcv($sock_b, $port_a, rtpm(96, $seq + 10, 7200, 0x5678, "\xf0\x1c\x50\x54\x30\x77\xf3\xdd\x1d\xd3\x57\x6b\xce\xc7\xcd\x7a\x17\x71\x05\x36\x04\x42\x70\x72\x73\x25\x0c\x14\x26\x2a\x05\x72\x03\x90\xf2\x5c\x48\xd8"));
 
 # inject old PCM
+$resume_time = Time::HiRes::time();
 snd($sock_a, $port_b, rtp(0, 2004, 5120, 0x5678, "\x40" x 160));
 snd($sock_a, $port_b, rtp(0, 2006, 5440, 0x5678, "\x40" x 160));
 # packet dropped
 rcv_no($sock_b);
+# Make the elapsed gap large enough to distinguish it from a single 20 ms increment.
+Time::HiRes::usleep(200000);
 
 # reinvite back to PCMU
 
@@ -762,9 +765,12 @@
 
 
 snd($sock_a, $port_b, rtp(0, 2007, 5760, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(96, $seq + 11, 7520, $ssrc, "\xf0\x1c\x21\x40\x00\xff\xfb\xfc\x92\x17\x2f\x21\x34\xcb\x60\x28\x1b\x23\x23\x30\x04\x87\xb1\x30\x4f\x91\x04\x5e\xd9\xc6\x6c\xfc\x28\xed\xe1\xc6\xd5\xe0"));
+# AMR-WB uses a 16 kHz output clock, independently of the G.711 input origin.
+($ts) = rcv($sock_b, $port_a, rtpm(96, $seq + 11, -1, $ssrc, "\xf0\x1c\x21\x40\x00\xff\xfb\xfc\x92\x17\x2f\x21\x34\xcb\x60\x28\x1b\x23\x23\x30\x04\x87\xb1\x30\x4f\x91\x04\x5e\xd9\xc6\x6c\xfc\x28\xed\xe1\xc6\xd5\xe0"));
+cmp_ok(abs(($ts - 7200) / 16000 - (Time::HiRes::time() - $resume_time)), '<', 0.1,
+        'AMR-WB output clock advances through codec reconfiguration');
 snd($sock_a, $port_b, rtp(0, 2007, 5920, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(96, $seq + 12, 7840, $ssrc, "\xf0\x1c\xc8\xc6\x04\x55\x92\x65\x07\x9c\x21\x19\x06\x71\x89\xd4\x66\xe6\x84\xe6\xc5\xc4\xc4\xcc\x5e\xc1\xc5\xf5\x4c\x55\xde\x71\x9a\x57\xc0\xde\xe4\xd0"));
+rcv($sock_b, $port_a, rtpm(96, $seq + 12, $ts + 320, $ssrc, "\xf0\x1c\xc8\xc6\x04\x55\x92\x65\x07\x9c\x21\x19\x06\x71\x89\xd4\x66\xe6\x84\xe6\xc5\xc4\xc4\xcc\x5e\xc1\xc5\xf5\x4c\x55\xde\x71\x9a\x57\xc0\xde\xe4\xd0"));
 
 rtpe_req('delete', 'G.711/AMR-WB codec change reverse', { 'from-tag' => ft() });
 
@@ -894,6 +900,7 @@
 rcv($sock_b, $port_a, rtpm(8, $seq + 10, 5600, 0x5678, "\xd5\xd5\xd5\xd5\x55\x55\xd5\x55\x55\xd5\x55\x55\x55\x55\xd5\x55\x55\xd5\x55\xd5\x55\xd5\x55\x55\xd5\xd5\xd5\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\xd5\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\xd5\x55\x55\xd5\x55\x55\x55\x55\x55\x55\x55\xd5\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\xd5\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\xd5\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\x55\xd5\xd5\xd5\xd5\xd5\xd5\xd5\x55\x55\x55\x55\x55\x55\x55"));
 
 # inject old PCM
+$resume_time = Time::HiRes::time();
 snd($sock_a, $port_b, rtp(0, 2006, 5760, 0x5678, "\x40" x 160));
 # packet dropped
 rcv_no($sock_b);
@@ -947,9 +954,12 @@
 
 
 snd($sock_a, $port_b, rtp(0, 2007, 5920, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(8, $seq + 11, 5760, $ssrc, "\x68" x 160));
+# Reconfiguration retains elapsed time in the output clock, independently of the input origin.
+($ts) = rcv($sock_b, $port_a, rtpm(8, $seq + 11, -1, $ssrc, "\x68" x 160));
+cmp_ok(abs(($ts - 5600) / 8000 - (Time::HiRes::time() - $resume_time)), '<', 0.1,
+        'output clock advances through codec reconfiguration');
 snd($sock_a, $port_b, rtp(0, 2008, 6080, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(8, $seq + 12, 5920, $ssrc, "\x68" x 160));
+rcv($sock_b, $port_a, rtpm(8, $seq + 12, $ts + 160, $ssrc, "\x68" x 160));
 
 rtpe_req('delete', 'G.711/AMR-WB codec change with timing', { 'from-tag' => ft() });
 
@@ -1081,6 +1091,7 @@
 rcv($sock_b, $port_a, rtpm(8, $seq + 10, 5600, 0x5678, "\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5\xd5"));
 
 # inject old PCM
+$resume_time = Time::HiRes::time();
 snd($sock_a, $port_b, rtp(0, 2006, 5600, 0x5678, "\x40" x 160));
 # packet dropped
 rcv_no($sock_b);
@@ -1134,7 +1145,10 @@
 
 
 snd($sock_a, $port_b, rtp(0, 2007, 5760, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(8, $seq + 11, 5760, $ssrc, "\x68" x 160));
+# Reconfiguration retains elapsed time in the output clock, independently of the input origin.
+($ts) = rcv($sock_b, $port_a, rtpm(8, $seq + 11, -1, $ssrc, "\x68" x 160));
+cmp_ok(abs(($ts - 5600) / 8000 - (Time::HiRes::time() - $resume_time)), '<', 0.1,
+        'output clock advances through codec reconfiguration');
 
 rtpe_req('delete', 'G.711/AMR codec change with timing', { 'from-tag' => ft() });
 
@@ -2044,14 +2058,17 @@
 	rcv($sock_b, $port_a, rtpm(8, $seq + 9 + $i, 5440 + $i * 160, $ssrc, "\xd5" x 160));
 }
 # now shut down
+$resume_time = Time::HiRes::time();
 rcv_no($sock_b);
 # start audio again
 snd($sock_a, $port_b, rtp(0, 2005, 90000, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(8, $seq + 507, 90000, $ssrc, "\x68" x 160));
+($ts) = rcv($sock_b, $port_a, rtpm(8, $seq + 507, -1, $ssrc, "\x68" x 160));
+cmp_ok(abs(($ts - (5440 + 497 * 160)) / 8000 - (Time::HiRes::time() - $resume_time)), '<', 0.1,
+        'output clock survives maximum DTX shutdown');
 snd($sock_a, $port_b, rtp(0, 2006, 90160, 0x5678, "\x40" x 160));
-rcv($sock_b, $port_a, rtpm(8, $seq + 508, 90160, $ssrc, "\x68" x 160));
+rcv($sock_b, $port_a, rtpm(8, $seq + 508, $ts + 160, $ssrc, "\x68" x 160));
 # DTX -> silence
-rcv($sock_b, $port_a, rtpm(8, $seq + 509, 90320, $ssrc, "\xd5" x 160));
+rcv($sock_b, $port_a, rtpm(8, $seq + 509, $ts + 320, $ssrc, "\xd5" x 160));
 
 rtpe_req('delete', 'G.711 DTX ptime change', { 'from-tag' => ft() });