In need for help. ALESIS iO2 Interface Inputs do not work anymore

Hi everybody!

The most incredible thing happened last evening. I was trying to record vocals with my system consisting from athe laptop Sony VAIO, Alesis iO2, condenser mic Oktava MK-319 and SONAR 6.2...
It all started very nice, but as I recorded two of the three verses, the level of the mic signal began to decrease and then had finally disappeared at all! I tried another channel of the interface. It worked for about two minutes constantly decreasing just before my eyes! Incredible!

I do not know what happened. I tried to switch to Cubase. No signal at all, either.
However, the indicators on the interface work and show the input. Output is also OK. Just no input.
I reinstalled the drivers. No luck...
In SONAR's settings everything looks OK.

Could it be an OS problem (I use Vista)? Well, after all it had been alright for several months before tonight.

Friends, if anyone knows something, please help!

I have an urgent project to finish and I feel frustrated due to this irritating problem.
I've just spent more than 300 bucks on new monitors and more on studio furniture... don't have more money to buy a new interface...

Many thanks in advance!