Comment 8 for bug 513069

I have a very similar problem on an HP g62 with 10.04 x86_64. Same Radeon HD 4200 sound device too. It appears that Intel's HDA driver gets loaded for it.

01:05.1 Audio device: ATI Technologies Inc RS880 Audio Device [Radeon HD 4200]
 Subsystem: Hewlett-Packard Company Device 1444
 Flags: bus master, fast devsel, latency 0, IRQ 19
 Memory at d0310000 (32-bit, non-prefetchable) [size=16K]
 Capabilities: [50] Power Management version 3
 Capabilities: [a0] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
 Kernel driver in use: HDA Intel
 Kernel modules: snd-hda-intel

Full output of lspci -v attached.