AC Relay EMI Suppression

[mister_e]

you can do many many many many things...

the intelligent and easy solution is to activate and deactivate the relays when the AC signal line cross the zero volt.

Use separate ground lines for your relay and for the digital section of your design.

Be sure all your PIC pins are tie somewhere. Floating pins cause also many problem in noisy environement. Internal pull-up or set the unused i/o to output like Microchip suggest do absolutely nothing good.

if you can post your whole schematic and layout we can also suggest some things.