To all of you. I had this same issue with most dialers in the kitchen. I changed my dialer to the iphone minimal dialer or whatever it's called, and it fixes the issue every time. Not quite sure what's causing it, but It's something to do with the dialers and the newer ROM Builds. I noticed the issue since Build 20226.
Try building your ROM with the iphone minimal dialer and see if that fixes your problem
By the way, I'm using Radio Version 3.42.50 and ROM Build 20748 from the ppckitchen.org Kitchen