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View Full Version : How does synch work? (squeezlite + 2x SB)



ezekieldas
2013-03-01, 20:26
My setup is this: LMS 7.7.2 on Linux w/squeezelite out via SPDIF to local amp + 2x SB. The SB are always in synch. However, every other day I have to synch the squeezelite
stream with the SB boxen. Naturally there's latency to consider over the wirless connection so that makes sense. BUT what I do not get is:

I go to Player -> squeezelite -> Synchronize -> Player Audio Delay (ms)

Sometimes I increment sometimes I decrement. There doesn't seem to be any consistent pattern here. Sometimes I adjust Player Start Delay (ms) a bit and that seems to help. Sometimes
it doesn't. So my question is how does this work really? Why does this only work when I delay the device with the least latency? Is there anything I can do to keep from having to do this every other day? And lastly, if this is a regular tunable... has anyone automated it via curl or cron based CLI?

toby10
2013-03-02, 04:14
.... Is there anything I can do to keep from having to do this every other day? ...

Not likely. The Synch is being affected by the computer running SqueezeLite (software, drivers, audio card, etc...).

epoch1970
2013-03-02, 07:43
You can try reducing the alsa buffer time in squeezelite. I have good synching results with "-a 10:4::1", and even 8. I think the player defaults to 20. If you go too low, you'll get audio glitches. If I read the 10:4 right, it means alsa sends an interrupt and reads its buffer every 2,5 milliseconds…
Audio delay didn't really help me either. Start delay (as found on SB3) is not implemented but I wouldn't guess this could be useful or not.
If you're using a small CPU, too much load at song startup may cause bad sync for a few secs. I don't think there is any way around that.