HELP: Toshiba Tecra 9100

Greetings,
I have a fairly interesting problem.

I have a Tecra 9100 - approx 3 years now under warranty. Towards the
end of the term, the internal wireless, sound and power management went
out.

Took it to Toshiba authorized service center, they replaced:
* keyboard
* wireless module
* motherboard
* sound board

computer obviously worked great when I got it back, this was about 6
months ago. Here is where it gets weird.

About 3 weeks ago, the exact same thing has happened. No sound,
wireless or power mgmt.

I have not installed any new software since I got the laptop back 6
months ago.

The Toshiba Wireless software runs its self tests and reports
everything is working fine, which of course it is not.

I realize I am S.O.L as far as getting any hardware repaired/replaced
but I find it more than interesting that the same thing has happened.

I though well maybe since I have Windows 2000 automatic updates on,
perhaps it installed something the computer did not like.

So... I booted off of a Knoppix cd and same situation.... no sound,
wireless or PM.

Just wondering if anyone might have some thoughts on this?

I also heard a crackling sound coming out of the speakers both times
this has happened though I was doing nothing on the computer as far as
applications, it was just on my desk turned on.

Well thanks for your time.

--Jeff