PWM and audio noise

[Scampy]

I'm no expert, but most analogue audio signals alternate between + and - rails and thus are not "grounded" in the same way as supply rails. But you have said that separating them hasn't resolved the problem. Possibly some grounded shielding over the PIC to prevent RF interference might help

[Charlie]

This is always caused by either the design or layout. Post the schematic and layout if you really want an answer.

[Art]

You haven’t described what you’re doing, or how the RF relates to the PWM.
For all we know you’re clocking a pic at 10MHz and sending the audio out of a 10MHz WWV receiver through audio on the board.

[Normnet]

A simple software change to try is to rearrange the order of the variables as they are declared. This worked for me although on a different compiler the app did utilize PWM as an audio output. Hope this helps.

Norm