OT: Audio Feedback Problem on Thinkpad T40

[R. G. Newbury]

Booted my Thinkpad T40 this morning and it immediately started a high 
pitched feedback squeal. The volume controls do nothing and of course 
there is nothing in the BIOS section to even attempt to control or 
change the behaviour. Interestingly, it also seems to affect CPU usage: 
the machine is very slow in responding to inputs, but top shows nothing 
out of the ordinary.

Anyone have any thoughts about what is going on?

G.