[notz]

I'm running "xbmcbuntu-11.9-wsnipex-testing-v7.iso" from Xbmcfreak on an Acer Revo 3610 with audio over HDMI to a 5.1 channel amp. Sound is working fine for both music and videos.

However in the XBMC interface, with nothing playing, the audio device gets reopened every 10 seconds which causes the AV amp to resync. The following is repeated every 10 seconds in the log:

Code:

14:06:19 T:2941307712   DEBUG: CSoftAE::Run - Sink restart flagged
14:06:19 T:2941307712    INFO: CSoftAE::InternalOpenSink - sink incompatible, re-starting
14:06:19 T:2941307712    INFO: CAESinkALSA::Initialize - Attempting to open device "hdmi:CARD=NVidia,DEV=0"
14:06:19 T:2941307712    INFO: CAESinkALSA::Initialize - Opened device "hdmi:CARD=NVidia,DEV=0,AES0=0x04,AES1=0x82,AES2=0x00,AES3=0x00"
14:06:19 T:2941307712    INFO: CAESinkALSA::InitializeHW - Your hardware does not support AE_FMT_FLOAT, trying other formats
14:06:19 T:2941307712    INFO: CAESinkALSA::InitializeHW - Using data format AE_FMT_S32NE
14:06:19 T:2941307712   DEBUG: CAESinkALSA::InitializeHW - Request: periodSize 512, periods 16, bufferSize 8192
14:06:19 T:2941307712   DEBUG: CAESinkALSA::InitializeHW - Got: periodSize 512, periods 16, bufferSize 8192
14:06:19 T:2941307712   DEBUG: CAESinkALSA::InitializeHW - Setting timeout to 186 ms
14:06:19 T:2941307712    INFO: CSoftAE::InternalOpenSink - ALSA Initialized:
14:06:19 T:2941307712    INFO:   Output Device : HDA NVidia
14:06:19 T:2941307712    INFO:   Sample Rate   : 44100
14:06:19 T:2941307712    INFO:   Sample Format : AE_FMT_S32NE
14:06:19 T:2941307712    INFO:   Channel Count : 2
14:06:19 T:2941307712    INFO:   Channel Layout: FL,FR
14:06:19 T:2941307712    INFO:   Frame Size    : 8
14:06:19 T:2941307712   DEBUG: CSoftAE::InternalOpenSink - Using speaker layout: 5.1
14:06:19 T:2941307712    INFO: CAESinkALSA - ALSA: pcm_hw.c:587:(snd_pcm_hw_start) SNDRV_PCM_IOCTL_START failed (-32): Broken pipe

Full log here: http://pastebin.com/YbMGXZfx

While this is happening CPU usage is around 25-30%.

Any ideas?

You are not alone. I seek it's a common problem on linux/alsa (or only with nvidia chips). It seems that AE devs mainly don't use linux/alsa.
Perhaps it's related to this PR https://github.com/xbmc/xbmc/pull/1548. Their is 10sec timeout mentioned in comments.

2) "soft" Suspend - slips into idle mode 10 seconds after last stream or sound played - reduces battery consumption / CPU load and releases audio context as above. Signified by m_softSuspend == true && 10 sec delay elapsed.