Hi,
But that's the thing. You're quoting "the same" paragraph of the datasheet as I was but in "your" datasheet it says 37kHz, while in "mine" it says 48kHz. One of them is wrong or they've changed the silicon (unlikely). I'm not saying mine's correct and your's wrong (actually perhaps I am....) just that there is an inconsistency and that the 37kHz you might think you're running at might not be 37kHz.

The one I'm reading is called DS40044F and is dated 2007. Is it possible that you're looking at either an old version (prior to revision C is my guess) of the datasheet OR perhaps a version for the 16F628 (non A version?)

Anyway, good luck with the project!

/Henrik.