Audio Delay issues

1st Official Post

    Hi

    Been running LibreElec on a pi2 for quite a while, its a wonderful thing.

    However, had a SD card failure so decided to upgrade the system.

    Now using a pi3B+, booting LibreElec v9 Leia from an external USB drive I had lying around. Installed mpg2 and VC1 codecs from pi foundation.

    The rest is set up as before: media all stored on a NAS, connected to the pi via ethernet cable. Pi connected to TV via HDMI, and sound transferred from TV to AV receiver via optical link.

    Unfortunately, several of my video files now have delayed sound. It doesn't seem to be a problem with all files, but some mp4s have a delay of maybe 500ms on the sound. Movies (mostly DVD rips as .vob) have delays of anything from 200ms to about 1s.

    Settings as follows:

    output device: PI HDMI

    Channels: 2.0

    Output config: optimised

    Resample quality: medium

    Allow passthrough: On

    DD (AC3) Receiver: On

    DD AC3 transcoding: On

    Any thoughts?

    Also: I tried playing the pi directly to the AV receiver by HDMI, hoping this may solve the problem. Got picture but no sound at all this time!

    • Official Post

    It sounds like a decoding issue on your video files.

    If you could share a snippet of an offending file (If legal to do so) we could try and replicate the issue.

    Unfortunately I couldn't figure out how to cut a snippet from the files without changing them.

    However, if it helps I tried to run them on my laptop using VLC, and got the message that there was a problem with 'm2v1' format.

    (This is weird, as these files played fineusing the older version of LE on my pi2).

    Attempting a work-around by re-converting files into mp4 - will check tonight if they will now play OK.