I don't know Sylvio,
I'm running it here and I don't see the same problem.

But then, I've got a 16F887. Apples and Oranges...

Timer1 runs at 4khz, and the IF block executes once after each FLAG, so it runs at 4khz too.

The whole "block" including the LOOKUP and SAIDA: takes about 70us, so it's not taking too long.

Unless there's something in the part of the program that wasn't posted. I'm stumped.
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