T20 sound problems

[DaveB]

I have bought a T20 through ebay, it is running W2k and everything works apart from the sound. I get beeps from BIOS inputs ie volume buttons but nothing via W2k. It is a crystal fusion card running the latest drivers, latest BIOS etc. Windows reports no problems and plays sounds as if nothing is wrong but nothing comes out of the speakers. The modem dialing sound comes out of the laptop speakers so they must be working. Have tried external speakers - still no sound
Is there any way to test the sound card? can I connect an external sound device, USB,PCMCIA?
Have tried a fresh install of XP on a spare HD - still the same even though XP founf the sound card and loaded drivers ( if the card was faulty surely XP wouldn't find it and load drivers )
any info greatfully recieved as I'm going mad trying to get mt T20 to speak to me !!!!!
Dave