hdmi passthrough sync issue

[Thomas Green]

I have a device that I'm trying to pass hdmi input to hdmi output, and am having trouble with the audio and video gradually going out of sync; the audio starting to lag the video.

It is done with two separate pipelines:

gst-launch-0.10 nv4l2src device=/dev/video1 ! video/x-nv-yuv, width=1920, height=1072, format="(fourcc)I420", framerate="60/1" ! nvvidconv ! video/x-nv-yuv, width=1920, height=1072, format="(fourcc)I420", framerate="60/1" ! nv_omx_videosink hdmi=TRUE sync=TRUE

gst-launch-0.10 alsasrc device=plughw:0,2 do-timestamp=TRUE latency-time=100000 ! audio/x-raw-int, rate=48000, channels=2, width=16, depth=16 ! alsasink device=plughw:0,1 sync=FALSE qos=TRUE

where /dev/video1 is the v4l2 hdmi input device, and plughw:0,2 and plughw:0,1 the alsa hdmi input and out devices respectively.

I've tried to set sync=TRUE on the hdmi audio output to try to keep the audio in sync, but it either never starts sending audio, or after 5 to 15 minutes, the audio stops.

How can I keep the pipelines in sync and playing?


Tom