Many thanks for the quick response Moe. I double checked everything was unmuted and there was only one mic input. Here's what those commands produced in output:
[email protected]:~$ cat /proc/asound/cards
0 [Generic ]: HDA-Intel - HD-Audio Generic
HD-Audio Generic at 0xfeb44000 irq 45
1 [SB ]: HDA-Intel - HDA ATI SB
HDA ATI SB at 0xfeb40000 irq 16
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[email protected]:~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: Generic [HD-Audio Generic], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: SB [HDA ATI SB], device 0: ALC269VB Analog [ALC269VB Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
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[email protected]:~$ lspci -vv | grep -i -A10 audio
00:01.1 Audio device: ATI Technologies Inc Device 1314
Subsystem: ASUSTeK Computer Inc. Device 103b
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin B routed to IRQ 45
Region 0: Memory at feb44000 (32-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: HDA Intel
Kernel modules: snd-hda-intel
--
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) (rev 40)
Subsystem: ASUSTeK Computer Inc. Device 103b
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=slow >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 32, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 16
Region 0: Memory at feb40000 (64-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: HDA Intel
Kernel modules: snd-hda-intel
(1) ATI R6XX HDMI: empty / no controls or audio channels shown, but with the IEC958 box checked
However, the ALSA Mixer on my own computer similarly shows an empty tab for ATI (in this case ATI 690/780 HDMI) and full controls on the Realtek tab (in this case ALC 271X) and sound works fine.