Ubuntu 9.10 no sound

I have just installed 9.10 on a IBM T40 laptop. (approx 5yrs old)
Everything works well, except there is no sound.
I have checked the obvious things, muted etc.

Results of lspci are shown below

00:1f.5 Multimedia audio controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) AC'97 Audio Controller (rev 01)
 Subsystem: IBM Device 0537
 Flags: bus master, medium devsel, latency 0, IRQ 11
 I/O ports at 1c00 [size=256]
 I/O ports at 18c0 [size=64]
 Memory at c0000c00 (32-bit, non-prefetchable) [size=512]
 Memory at c0000800 (32-bit, non-prefetchable) [size=256]
 Capabilities: <access denied>
 Kernel driver in use: Intel ICH
 Kernel modules: snd-intel8x0

I have seen many threads, but can't make much sense of them.
I am very new to this, but can normally work pc issues out ok.

Please help with simple instructions