Unfortunately, I still haven't figured out a way to fix it and have done all the steps you listed. I've started to kick around the idea of replacing the unit all together. If the Android Auto units were cheaper, it'd be already done. I tried relocating the GPS antenna, but that didn't seem to have any effect. The only sound sources that don't lag are SiriusXM and HD Radio.

I wonder what the cost would be if I sent it back to Kenwood, or if they'd service it at all since I messed with the maps.