[mythtv-users] Airplay Sync with Multiple Devices - Mythtv only one out of sync

[Bob H.]

I was hoping someone might have an idea of how to fix a sync issue that 
occurs when airplay-ing to my frontend.
I am playing from itunes on a Windows-7 (x64) box to a laptop frontend 
(32-bit mythbuntu) and an airport speakers.
The Win-7 and airport speaks stay in sync perfectly, but the 
mythtv-frontend lags and this gets worse the longer playback continues.

$ mythfrontend --syslog local7 -v audio,playback --loglevel debug

See full logfile at the link below:
http://pastebin.com/R8EUUpNs


I get lots of messages like:
2012-12-18 20:57:14.103510 D RAOP Conn: Receiving SYNC packet
2012-12-18 20:57:14.103576 D RAOP Conn: SYNC: cur:40656486 next:40658494 
time:18446744072392920183
2012-12-18 20:57:14.103631 D RAOP Conn: Queue=153 buffer=2002ms 
ideal=2008ms diffts:-22ms
2012-12-18 20:57:15.386744 D RAOP Conn: Receiving SYNC packet
2012-12-18 20:57:15.386775 D RAOP Conn: SYNC: cur:40657492 next:40659500 
time:18446744072392921466
2012-12-18 20:57:15.386809 D RAOP Conn: Queue=153 buffer=2281ms 
ideal=2008ms diffts:256ms
2012-12-18 20:57:16.452767 I ALSA: WriteAudio: buffer underrun
2012-12-18 20:57:16.455667 D RAOP Conn: Receiving SYNC packet
2012-12-18 20:57:16.455692 D RAOP Conn: SYNC: cur:40658497 next:40660505 
time:18446744072392922535
2012-12-18 20:57:16.455716 D RAOP Conn: Queue=280 buffer=2345ms 
ideal=2008ms diffts:60ms
2012-12-18 20:57:16.574192 I ALSA: WriteAudio: buffer underrun
2012-12-18 20:57:16.706553 I ALSA: WriteAudio: buffer underrun
2012-12-18 20:57:16.818057 I ALSA: WriteAudio: buffer underrun
2012-12-18 20:57:17.530764 D RAOP Conn: Receiving SYNC packet
2012-12-18 20:57:17.530802 D RAOP Conn: SYNC: cur:40659503 next:40661511 
time:18446744072392923610
2012-12-18 20:57:17.530841 D RAOP Conn: Queue=203 buffer=2385ms 
ideal=2008ms diffts:-42ms
2012-12-18 20:57:18.126676 D RAOP Conn: Receiving SYNC packet
2012-12-18 20:57:18.126716 D RAOP Conn: SYNC: cur:40660509 next:40662517 
time:18446744072392924206
2012-12-18 20:57:18.126764 D RAOP Conn: Queue=207 buffer=2002ms 
ideal=2008ms diffts:-451ms
2012-12-18 20:57:19.341988 D RAOP Conn: Receiving SYNC packet
2012-12-18 20:57:19.342022 D RAOP Conn: SYNC: cur:40661515 next:40663523 
time:18446744072392925422
2012-12-18 20:57:19.342059 D RAOP Conn: Queue=192 buffer=2097ms 
ideal=2008ms diffts:-242ms