I can post the program, but it's pretty convoluted and may be hard to follow as it has 'grown' as I've added functionality. It interacts with a rotary encoder, a couple of switches, a DSP, a AM/FM tuner IC, and a stepper motor. I'm a hardware guy, who knows enough to comment and use sub's, but am not a software person by nature or training. So the structure may be sub optimal, at the least.
I guess the question I have is..Is it possible that the compiler is creating this problem, or is it something about the interrupt assembly code, or should I continue to look for an error in my code?
Anyway, if someone wants to look at it I'll post it here.