<html><head></head><body><div class="ydpf014c9e8yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div dir="ltr" data-setdir="false">I've been trying to solve this issue for several days but just cant fix.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">I have 2 Raspberry pi CM4 systems (both identical OS) locked together</div><div dir="ltr" data-setdir="false">with ptp4l. I have got a nice low-latency rtp stream sending 48k 24 bit audio from 1 to another.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">I'm using the audiotestsrc in gstreamer to generate tone bursts so I can look at the signal on my scope from</div><div dir="ltr" data-setdir="false">each device and see the latency/sync.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">The commands below seem to work well - no glitches and very low latency(approx 8 mS)</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">But on the receiver the latency gradually increases. It seems to go up by about 1mS per 3 minutes.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">TRANSMIT:</div><div dir="ltr" data-setdir="false"><span><div>gst-launch-1.0 -vv audiotestsrc is-live=true wave=ticks apply-tick-ramp=true tick-interval=100000000 freq=10000 volume=0.5 sine-periods-per-tick=100 ! audioconvert ! audio/x-raw, format=S24LE, rate=48000, channels=2 ! tee name=t ! audioconvert ! queue ! rtpL24pay ! udpsink host=239.255.0.10 t. ! queue ! alsasink</div><div><br></div><div dir="ltr" data-setdir="false">RECEIVE:</div><div dir="ltr" data-setdir="false"><span><div>gst-launch-1.0 udpsrc address=239.255.0.10 port=5004 multicast-iface=eth0 ! application/x-rtp, clock-rate=48000, channels=2 ! rtpjitterbuffer latency=5 ! rtpL24depay ! audioconvert ! alsasink processing-deadline=0 latency-time=1 buffer-time=1</div></span></div></span></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Do these look ok?</div><div dir="ltr" data-setdir="false">Maybe I need to be clocking the receiver from the incoming stream somehow?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">TIA</div><div><br></div><div class="ydpf014c9e8signature"><br></div></div></body></html>