Alsa
為什麼aplay在speaker-test的時候不能播放4或6聲道的聲音？
我目前正在嘗試設置 Soundblaster 卡（CA106 晶片組）以輸出到 4 個通道。
我將 4 個揚聲器插入模擬輸出（使用插頭）。
當我使用該
speaker-test實用程序測試 pseakers 時，它執行良好，但每當我嘗試使用實用程序播放 4 聲道（由我自己建構）或任何多聲道聲音（從網路檢索）時，aplay我都無法讓它工作。這是有關我的硬體設置的資訊：
[root@server SurroundTestFiles]# aplay -L default:CARD=CA0106 CA0106, CA0106 Default Audio Device front:CARD=CA0106,DEV=0 CA0106, CA0106 Front speakers rear:CARD=CA0106,DEV=0 CA0106, CA0106 Rear speakers center_lfe:CARD=CA0106,DEV=0 CA0106, CA0106 Center and Subwoofer speakers side:CARD=CA0106,DEV=0 CA0106, CA0106 Side speakers surround40:CARD=CA0106,DEV=0 CA0106, CA0106 4.0 Surround output to Front and Rear speakers surround41:CARD=CA0106,DEV=0 CA0106, CA0106 4.1 Surround output to Front, Rear and Subwoofer speakers surround50:CARD=CA0106,DEV=0 CA0106, CA0106 5.0 Surround output to Front, Center and Rear speakers surround51:CARD=CA0106,DEV=0 CA0106, CA0106 5.1 Surround output to Front, Center, Rear and Subwoofer speakers surround71:CARD=CA0106,DEV=0 CA0106, CA0106 7.1 Surround output to Front, Center, Side, Rear and Woofer speakers iec958:CARD=CA0106,DEV=0 CA0106, CA0106 IEC958 (S/PDIF) Digital Audio Output null Discard all samples (playback) or generate zero samples (capture) default:CARD=Intel HDA Intel, AD198x Analog Default Audio Device front:CARD=Intel,DEV=0 HDA Intel, AD198x Analog Front speakers surround40:CARD=Intel,DEV=0 HDA Intel, AD198x Analog 4.0 Surround output to Front and Rear speakers surround41:CARD=Intel,DEV=0 HDA Intel, AD198x Analog 4.1 Surround output to Front, Rear and Subwoofer speakers surround50:CARD=Intel,DEV=0 HDA Intel, AD198x Analog 5.0 Surround output to Front, Center and Rear speakers surround51:CARD=Intel,DEV=0 HDA Intel, AD198x Analog 5.1 Surround output to Front, Center, Rear and Subwoofer speakers surround71:CARD=Intel,DEV=0 HDA Intel, AD198x Analog 7.1 Surround output to Front, Center, Side, Rear and Woofer speakers hdmi:CARD=Intel,DEV=0 HDA Intel HDMI Audio Output [root@server SurroundTestFiles]# alsacard 0 [root@server SurroundTestFiles]# cat /proc/asound/cards 0 [CA0106 ]: CA0106 - CA0106 Audigy SE [SB0570] at 0xcce0 irq 169 1 [Intel ]: HDA-Intel - HDA Intel HDA Intel at 0xf7ffc000 irq 82這是我在兩種情況下都使用的命令（以及相應的輸出）。
揚聲器測試：
speaker-test -c 4 -D surround40:CA0106 -t wav這會將正確的聲音吐到正確的揚聲器（4 聲道到 4 揚聲器）
這是
aplay嘗試使用相同的虛擬設備 (surround40) 播放 4 聲道聲音時的輸出：[root@epr-servmcs-40 SurroundTestFiles]# aplay -v -D surround40:CA0106 -c 4 test-4-channels.wav Playing WAVE 'test-4-channels.wav' : Signed 24 bit Little Endian in 3bytes, Rate 44100 Hz, Channels 4 aplay: set_params:954: Sample format non available如果我嘗試在
aplay未明確指定設備的情況下使用它僅在 2 個揚聲器上播放聲音，請參閱此測試的輸出：[root@epr-servmcs-40 SurroundTestFiles]# aplay -v -c 4 test-4-channels.wav Playing WAVE 'test-4-channels.wav' : Signed 24 bit Little Endian in 3bytes, Rate 44100 Hz, Channels 4 Plug PCM: Route conversion PCM (sformat=S24_3LE) Transformation table: 0 <- 0 1 <- 1 Its setup is: stream : PLAYBACK access : RW_INTERLEAVED format : S24_3LE subformat : STD channels : 4 rate : 44100 exact rate : 44100 (44100/1) msbits : 24 buffer_size : 7526 period_size : 940 period_time : 21333 tstamp_mode : NONE period_step : 1 avail_min : 940 period_event : 0 start_threshold : 7526 stop_threshold : 7526 silence_threshold: 0 silence_size : 0 boundary : 986447872 Slave: Rate conversion PCM (48000, sformat=S32_LE) Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S24_3LE subformat : STD channels : 2 rate : 44100 exact rate : 44100 (44100/1) msbits : 24 buffer_size : 7526 period_size : 940 period_time : 21333 tstamp_mode : NONE period_step : 1 avail_min : 940 period_event : 0 start_threshold : 7526 stop_threshold : 7526 silence_threshold: 0 silence_size : 0 boundary : 986447872 Slave: Direct Stream Mixing PCM Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S32_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 32 buffer_size : 8192 period_size : 1024 period_time : 21333 tstamp_mode : NONE period_step : 1 avail_min : 1024 period_event : 0 start_threshold : 8192 stop_threshold : 8192 silence_threshold: 0 silence_size : 0 boundary : 1073741824 Hardware PCM card 0 'CA0106' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S32_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 32 buffer_size : 8192 period_size : 1024 period_time : 21333 tstamp_mode : ENABLE period_step : 1 avail_min : 1024 period_event : 0 start_threshold : 1 stop_threshold : 1073741824 silence_threshold: 0 silence_size : 1073741824 boundary : 1073741824我的目標是強制（或允許）
aplay正確播放多聲道聲音（實際上只有 4 聲道聲音），我的意思是使用 4 個揚聲器。
.wav 文件使用您的硬體不支持的範例格式。
使用設備名稱
plug:surround40:CA0106啟用自動樣本格式轉換。要使其成為預設設備，
/etc/asound.conf請在您的 或中使用類似的東西~/.asoundrc：pcm.!default { type asym playback.pcm { type plug slave.pcm "surround40:CA0106" } capture.pcm { type plug slave.pcm "hw:CA0106" } }