In my impreza I have my steering wheel controls connected to my bt920 and for some reason my buttons my buttons lose functionality randomly. Once I lost volume up then mute. I am able to reprogram and it works again for a bit but then eventually they lose functionality again. I am using the pac swi-ps to connect my steering wheel controls to my unit.

Thanks in advance.

you may either have a bad connection, or a defective SWI. a far less likely cause could also be a failing clockspring. if it was a clockspring, everything on the wheel would/will soon be going bad (horn, airbag light on dash)