Hi Hank

I may be wrong here, but, my suspicion is you are losing time in reentering PBP in your ISRs. See, a lot of PBP registers have to be saved even if they are not going to be used because you flagged your ISR to be coded using PBP functions.

I suggest you slim it down by using ASM inside the ISR and avoiding ReEnterPbp. You should see better results.

I might sound like a heretic here, but I prefer coding my ISR in ASM even though it may be painful to code.

Regards