自从更新到 OSX Mavericks 后，我的蓝牙音频设备就出现了一个恼人的问题。当连接的蓝牙设备没有播放声音时，设备每三秒就会发出一次爆音。
我查看了蓝牙日志，发现系统似乎每三秒将设备置于省电模式，然后很快将其恢复。事实上，状态变化与砰砰声完全一致。
有人知道禁用此“功能”的信息吗？状态变化产生的爆音非常烦人。
如果我理解有误，日志如下：
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1988 Enqueue - BTStartIO for GT BT-Receiver
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:2000 Process next XPC command: 1
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:2092 ProcessXPC: startIO output (prev input:0 output:0)
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:983 Sample rate change 44100.000000->44100.000000
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:543 [prepareAudio] audioSink:1
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:633 [prepareAudio] Returning: 0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1103 [startAudio] sampleRate:44100.000000 isA2DPSink:1 SCOState:0 A2DPState:1 isSystemSleeping:0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1200 [startA2DPAudio] state:2
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:603 Sending Start
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:687 [startStream] mPairedEndpoint: 0x7fd54143d2a0, source: 1, state: 2
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:403 [testSetState] 2->3 returns 0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:1174 [Start] endpointID: 1
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:427 [setSignalInProgress] isInProgress: 1
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:438 [setSignalInProgress] setting up timer with timeout: 3.000000
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:318 [Fragment] entry Size: 3
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:374 [sendSignal] entry
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:348 [FragmentAndSendSignal] Ignored return:0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:711 [startStream] returning 0x0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:427 [setSignalInProgress] isInProgress: 0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:554 [AVDTP Response] -> Start
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamManager.m:422 START RESPONSE endpointID:1 acp-endpointID:63 status:0x0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:1682 START RESPONSE: 0x0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:403 [testSetState] 2->3 returns 0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:1364 [stateChanged] 3
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:435 [setStatusTimer] setting...
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:1183 [Start Complete]: 0x0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1103 [startAudio] sampleRate:44100.000000 isA2DPSink:1 SCOState:0 A2DPState:2 isSystemSleeping:0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1200 [startA2DPAudio] state:3
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1262 Streaming when already streaming?
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1423 initiateStreaming A2DPState:3
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:253 setSniffAllowed:0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1311 #ch:2 rate:44100 duration:0.011610
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:1306 [setDuration] duration: 0.011610 numFrames: 512
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1324 [setAudioFormat] Codec:0 returns 0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1463 [initiateStreaming] Current role is master
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:959 startAudioTransmit
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:1143 [recalculate] TXDelta: 0.007256 (MTU:672.000000 Se:118.000000 Ne:64.000000 Tx:0.011610 Nx:512.000000)
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1491 [initiateStreaming] exit 0x0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1517 [encodingThreadRoutine] going onto runloop
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1865 SendXPCResponse:0 replyMessage:1 xpcConnection:1 to method:BTStartIO
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:2000 Process next XPC command: 0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:1217 [Start Complete] returning: 0x0
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] AVSignalManager.m:690 [AVDTP Response] exit
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1565 Clear buffered audio
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:241 Stop IO - set outputActiveBeforeSleep = NO
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:1988 Enqueue - BTStopIO for GT BT-Receiver
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:2000 Process next XPC command: 1
Mon Mar 17 20:39:57 201 [bluetoothaudiod:2236] BluetoothAudio.m:2013 Delay stop for 3 seconds
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:2000 Process next XPC command: 1
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:2151 ProcessXPC: stopIO output. Input is 1
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:1152 stopAudio isSCOActive:0 (SCO:0 A2DP:3)
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:648 Sending Suspend
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:1386 [stopAudioEncoder]
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:1552 encodeCurrentAudioBlock stop
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:1523 [encodingThreadRoutine] exit
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:875 SetIsCommandInt: 1
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:403 [testSetState] 3->2 returns 0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:1261 [Suspend] endpointID: 1
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:427 [setSignalInProgress] isInProgress: 1
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:438 [setSignalInProgress] setting up timer with timeout: 3.000000
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:318 [Fragment] entry Size: 3
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:374 [sendSignal] entry
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:348 [FragmentAndSendSignal] Ignored return:0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:747 [suspendStream] returning 0x0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:427 [setSignalInProgress] isInProgress: 0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:554 [AVDTP Response] -> Suspend
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVStreamManager.m:451 SUSPEND RESPONSE endpointID:1 acp-endpointID:29 status:0x0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:1747 SUSPEND RESPONSE: 0x0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVStreamEndpoint.m:403 [testSetState] 3->2 returns 0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:1364 [stateChanged] 2
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:1257 [Suspend Complete]: 0x0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:253 setSniffAllowed:1
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:1386 [stopAudioEncoder]
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:1865 SendXPCResponse:0 replyMessage:0 xpcConnection:1 to method:BTStopIO
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudio.m:2000 Process next XPC command: 0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] BluetoothAudioAgent.m:1283 [Suspend Complete] returning: 0x0
Mon Mar 17 20:40:00 201 [bluetoothaudiod:2236] AVSignalManager.m:690 [AVDTP Response] exit
答案1
看起来没有人能为 Mavericks 解答这个问题，而且我搜寻了几个小时之后也没有找到任何其他东西。
好的一面是，这个问题在 Yosemite 开发者预览版中已经修复。