"Thanks. Any advice on the amp (brand and output) that I should replace the XPA with? Any help in the right direction is appreciated. I have about $1500- $2000 to invest in a new amp. Thanks again."
If you want some good advice, it would be to stop right there. If I'm reading your OP correctly, it looks like you have a real problem. The sound shouldn't just break up and disappear just because you are running your amp a little hard. Something is either not hooked up properly or broken (or both). You need to figure out what the problem is before you buy anything. Check everything. Look all of your components and cables over really well. Plug your sources into different inputs on your preamp. Swap components out with others. Basically, do everything you can do to isolate the problem. Don't do anything until you figure out, for sure, what's wrong.
Anyway, thats my advice.
If you want some good advice, it would be to stop right there. If I'm reading your OP correctly, it looks like you have a real problem. The sound shouldn't just break up and disappear just because you are running your amp a little hard. Something is either not hooked up properly or broken (or both). You need to figure out what the problem is before you buy anything. Check everything. Look all of your components and cables over really well. Plug your sources into different inputs on your preamp. Swap components out with others. Basically, do everything you can do to isolate the problem. Don't do anything until you figure out, for sure, what's wrong.
Anyway, thats my advice.