我使用的是带有两个完全相同的 USB 音频设备的 Raspberry PI。我想要做的是设置第一个 USB 设备始终为 hw:0,1，第二个设备始终为 hw:0,2。如果我移除设备并以不同的顺序插入它们，那么音频将会颠倒。我看了一下USB音频设备并在多声卡这似乎表明每个设备都有自己唯一的硬件 ID，但事实似乎并非如此。它只是一个非常垃圾的 USB 音频设备吗？以下是 lsusb -v 的输出
Bus 001 Device 010: ID 0d8c:000c C-Media Electronics, Inc. Audio Adapter
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x0d8c C-Media Electronics, Inc.
idProduct 0x000c Audio Adapter
bcdDevice 1.00
iManufacturer 0
iProduct 1 C-Media USB Headphone Set
iSerial 0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 253
bNumInterfaces 4
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xa0
(Bus Powered)
Remote Wakeup
MaxPower 100mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 1 Control Device
bInterfaceProtocol 0
iInterface 0
AudioControl Interface Descriptor:
bLength 10
bDescriptorType 36
bDescriptorSubtype 1 (HEADER)
bcdADC 1.00
wTotalLength 100
bInCollection 2
baInterfaceNr( 0) 1
baInterfaceNr( 1) 2
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 1
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bNrChannels 2
wChannelConfig 0x0003
Left Front (L)
Right Front (R)
iChannelNames 0
iTerminal 0
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 2
wTerminalType 0x0201 Microphone
bAssocTerminal 0
bNrChannels 1
wChannelConfig 0x0001
Left Front (L)
iChannelNames 0
iTerminal 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 6
wTerminalType 0x0301 Speaker
bAssocTerminal 0
bSourceID 9
iTerminal 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 7
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bSourceID 8
iTerminal 0
AudioControl Interface Descriptor:
bLength 7
bDescriptorType 36
bDescriptorSubtype 5 (SELECTOR_UNIT)
bUnitID 8
bNrInPins 1
baSource( 0) 10
iSelector 0
AudioControl Interface Descriptor:
bLength 10
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 9
bSourceID 15
bControlSize 1
bmaControls( 0) 0x01
Mute Control
bmaControls( 1) 0x02
Volume Control
bmaControls( 2) 0x02
Volume Control
iFeature 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 10
bSourceID 2
bControlSize 1
bmaControls( 0) 0x43
Mute Control
Volume Control
Automatic Gain Control
bmaControls( 1) 0x00
iFeature 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 13
bSourceID 2
bControlSize 1
bmaControls( 0) 0x03
Mute Control
Volume Control
bmaControls( 1) 0x00
iFeature 0
AudioControl Interface Descriptor:
bLength 13
bDescriptorType 36
bDescriptorSubtype 4 (MIXER_UNIT)
bUnitID 15
bNrInPins 2
baSourceID( 0) 1
baSourceID( 1) 13
bNrChannels 2
wChannelConfig 0x0003
Left Front (L)
Right Front (R)
iChannelNames 0
bmControls 0x00
iMixer 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 1
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
AudioStreaming Interface Descriptor:
bLength 7
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 1
bDelay 1 frames
wFormatTag 1 PCM
AudioStreaming Interface Descriptor:
bLength 14
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bNrChannels 2
bSubframeSize 2
bBitResolution 16
bSamFreqType 2 Discrete
tSamFreq[ 0] 48000
tSamFreq[ 1] 44100
Endpoint Descriptor:
bLength 9
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 9
Transfer Type Isochronous
Synch Type Adaptive
Usage Type Data
wMaxPacketSize 0x00c8 1x 200 bytes
bInterval 1
bRefresh 0
bSynchAddress 0
AudioControl Endpoint Descriptor:
bLength 7
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x01
Sampling Frequency
bLockDelayUnits 1 Milliseconds
wLockDelay 1 Milliseconds
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 1
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
AudioStreaming Interface Descriptor:
bLength 7
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 7
bDelay 1 frames
wFormatTag 1 PCM
AudioStreaming Interface Descriptor:
bLength 14
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bNrChannels 1
bSubframeSize 2
bBitResolution 16
bSamFreqType 2 Discrete
tSamFreq[ 0] 48000
tSamFreq[ 1] 44100
Endpoint Descriptor:
bLength 9
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 5
Transfer Type Isochronous
Synch Type Asynchronous
Usage Type Data
wMaxPacketSize 0x0064 1x 100 bytes
bInterval 1
bRefresh 0
bSynchAddress 0
AudioControl Endpoint Descriptor:
bLength 7
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x01
Sampling Frequency
bLockDelayUnits 0 Undefined
wLockDelay 0 Undefined
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 3
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 3 Human Interface Device
bInterfaceSubClass 0 No Subclass
bInterfaceProtocol 0 None
iInterface 0
HID Device Descriptor:
bLength 9
bDescriptorType 33
bcdHID 1.00
bCountryCode 0 Not supported
bNumDescriptors 1
bDescriptorType 34 Report
wDescriptorLength 50
Report Descriptors:
** UNAVAILABLE **
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x83 EP 3 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0004 1x 4 bytes
bInterval 32
Device Status: 0x0000
(Bus Powered)
Bus 001 Device 009: ID 0d8c:000c C-Media Electronics, Inc. Audio Adapter
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x0d8c C-Media Electronics, Inc.
idProduct 0x000c Audio Adapter
bcdDevice 1.00
iManufacturer 0
iProduct 1 C-Media USB Headphone Set
iSerial 0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 253
bNumInterfaces 4
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xa0
(Bus Powered)
Remote Wakeup
MaxPower 100mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 1 Control Device
bInterfaceProtocol 0
iInterface 0
AudioControl Interface Descriptor:
bLength 10
bDescriptorType 36
bDescriptorSubtype 1 (HEADER)
bcdADC 1.00
wTotalLength 100
bInCollection 2
baInterfaceNr( 0) 1
baInterfaceNr( 1) 2
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 1
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bNrChannels 2
wChannelConfig 0x0003
Left Front (L)
Right Front (R)
iChannelNames 0
iTerminal 0
AudioControl Interface Descriptor:
bLength 12
bDescriptorType 36
bDescriptorSubtype 2 (INPUT_TERMINAL)
bTerminalID 2
wTerminalType 0x0201 Microphone
bAssocTerminal 0
bNrChannels 1
wChannelConfig 0x0001
Left Front (L)
iChannelNames 0
iTerminal 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 6
wTerminalType 0x0301 Speaker
bAssocTerminal 0
bSourceID 9
iTerminal 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 3 (OUTPUT_TERMINAL)
bTerminalID 7
wTerminalType 0x0101 USB Streaming
bAssocTerminal 0
bSourceID 8
iTerminal 0
AudioControl Interface Descriptor:
bLength 7
bDescriptorType 36
bDescriptorSubtype 5 (SELECTOR_UNIT)
bUnitID 8
bNrInPins 1
baSource( 0) 10
iSelector 0
AudioControl Interface Descriptor:
bLength 10
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 9
bSourceID 15
bControlSize 1
bmaControls( 0) 0x01
Mute Control
bmaControls( 1) 0x02
Volume Control
bmaControls( 2) 0x02
Volume Control
iFeature 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 10
bSourceID 2
bControlSize 1
bmaControls( 0) 0x43
Mute Control
Volume Control
Automatic Gain Control
bmaControls( 1) 0x00
iFeature 0
AudioControl Interface Descriptor:
bLength 9
bDescriptorType 36
bDescriptorSubtype 6 (FEATURE_UNIT)
bUnitID 13
bSourceID 2
bControlSize 1
bmaControls( 0) 0x03
Mute Control
Volume Control
bmaControls( 1) 0x00
iFeature 0
AudioControl Interface Descriptor:
bLength 13
bDescriptorType 36
bDescriptorSubtype 4 (MIXER_UNIT)
bUnitID 15
bNrInPins 2
baSourceID( 0) 1
baSourceID( 1) 13
bNrChannels 2
wChannelConfig 0x0003
Left Front (L)
Right Front (R)
iChannelNames 0
bmControls 0x00
iMixer 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 1
bAlternateSetting 1
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
AudioStreaming Interface Descriptor:
bLength 7
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 1
bDelay 1 frames
wFormatTag 1 PCM
AudioStreaming Interface Descriptor:
bLength 14
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bNrChannels 2
bSubframeSize 2
bBitResolution 16
bSamFreqType 2 Discrete
tSamFreq[ 0] 48000
tSamFreq[ 1] 44100
Endpoint Descriptor:
bLength 9
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 9
Transfer Type Isochronous
Synch Type Adaptive
Usage Type Data
wMaxPacketSize 0x00c8 1x 200 bytes
bInterval 1
bRefresh 0
bSynchAddress 0
AudioControl Endpoint Descriptor:
bLength 7
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x01
Sampling Frequency
bLockDelayUnits 1 Milliseconds
wLockDelay 1 Milliseconds
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 0
bNumEndpoints 0
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 2
bAlternateSetting 1
bNumEndpoints 1
bInterfaceClass 1 Audio
bInterfaceSubClass 2 Streaming
bInterfaceProtocol 0
iInterface 0
AudioStreaming Interface Descriptor:
bLength 7
bDescriptorType 36
bDescriptorSubtype 1 (AS_GENERAL)
bTerminalLink 7
bDelay 1 frames
wFormatTag 1 PCM
AudioStreaming Interface Descriptor:
bLength 14
bDescriptorType 36
bDescriptorSubtype 2 (FORMAT_TYPE)
bFormatType 1 (FORMAT_TYPE_I)
bNrChannels 1
bSubframeSize 2
bBitResolution 16
bSamFreqType 2 Discrete
tSamFreq[ 0] 48000
tSamFreq[ 1] 44100
Endpoint Descriptor:
bLength 9
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 5
Transfer Type Isochronous
Synch Type Asynchronous
Usage Type Data
wMaxPacketSize 0x0064 1x 100 bytes
bInterval 1
bRefresh 0
bSynchAddress 0
AudioControl Endpoint Descriptor:
bLength 7
bDescriptorType 37
bDescriptorSubtype 1 (EP_GENERAL)
bmAttributes 0x01
Sampling Frequency
bLockDelayUnits 0 Undefined
wLockDelay 0 Undefined
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 3
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 3 Human Interface Device
bInterfaceSubClass 0 No Subclass
bInterfaceProtocol 0 None
iInterface 0
HID Device Descriptor:
bLength 9
bDescriptorType 33
bcdHID 1.00
bCountryCode 0 Not supported
bNumDescriptors 1
bDescriptorType 34 Report
wDescriptorLength 50
Report Descriptors:
** UNAVAILABLE **
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x83 EP 3 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0004 1x 4 bytes
bInterval 32
Device Status: 0x0000
(Bus Powered)