About six months ago we had a lightning strike and my FF400 has never been the same since.   I have had in for repair twice. The first time was for the firewire board/power supply I think. The second come to find out my power supply was toast.  The new power supply arrived yesterday and everything seemed fine. Until today. 

I started hearing audio slow down for 1/2 second maybe and then little cracks and glitches.  When it slows down it seems like it gets fast for a few milliseconds then plays again at a normal speed. It has little cracks and glitches more often.  Sometimes the slow down doesn't happen.  This was with iTunes and another mp3 player application.  Same thing this evening with Cubase.  My backup interface works fine, a TC Electronic Impact Twin, connected by the same cable I use for the FF400. 

I have a MacBook Pro 2.93 GHz Intel Core 2 Duo, 8 GB of memory running 10.6.7.  I was running 10.6.6 until an hour ago.  Same problem in either version.

iTunes has the problem less than Cubase.  But I had one track in Cubase for playback and one that I was recording to.  It happens in Cubase quite a bit.  It will be fine for 10 seconds then will glitch.  CPU and memory are very low.  I don't even see spikes when it happens in CPU or memory.  Anyone have any ideas I can try to resolve this?

The FF400 is at firmware 1.70 and the drivers are 2.91.  My 400 has been a workhorse for years on my Mac and an old Windows machine.  It just has not been the same since the lightning.