Есть древний трофейный SB Live 5.1. В линейный вход подключена гитара, в выход - наушники. Звук соответственно моно, причем только на левое ухо. Хочу, чтобы звук с линейного входа дублировался в оба уха наушников. Куда копать?
Выхлоп с `aplay -L`:
default:CARD=SB
HDA ATI SB, ALC888 Analog
Default Audio Device
sysdefault:CARD=SB
HDA ATI SB, ALC888 Analog
Default Audio Device
front:CARD=SB,DEV=0
HDA ATI SB, ALC888 Analog
Front speakers
surround40:CARD=SB,DEV=0
HDA ATI SB, ALC888 Analog
4.0 Surround output to Front and Rear speakers
surround41:CARD=SB,DEV=0
HDA ATI SB, ALC888 Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=SB,DEV=0
HDA ATI SB, ALC888 Analog
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=SB,DEV=0
HDA ATI SB, ALC888 Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=SB,DEV=0
HDA ATI SB, ALC888 Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=SB,DEV=0
HDA ATI SB, ALC888 Digital
IEC958 (S/PDIF) Digital Audio Output
hdmi:CARD=Generic,DEV=0
HD-Audio Generic, HDMI 0
HDMI Audio Output
default:CARD=Live
SB Live! 5.1, ADC Capture/Standard PCM Playback
Default Audio Device
sysdefault:CARD=Live
SB Live! 5.1, ADC Capture/Standard PCM Playback
Default Audio Device
front:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
Front speakers
rear:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
Rear speakers
center_lfe:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
Center and Subwoofer speakers
surround40:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
4.0 Surround output to Front and Rear speakers
surround41:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Live,DEV=0
SB Live! 5.1, ADC Capture/Standard PCM Playback
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
iec958:CARD=Live,DEV=0
SB Live! 5.1, Multichannel Capture/PT Playback
IEC958 (S/PDIF) Digital Audio Output
