My brother just had a Kenwood system installed in his Subaru Forrester. Nice big 10" and it supports Wireless Carplay. When he uses Waze or Apple Maps, the GPS is inaccurate and it shows his position off the road and the map zooms in and out over and over. He took it back and they "uncoiled" the gps antenna wire and placed the gps on the dashboard. He just started using it and he said GPS worked out for a minute or so but then started doing the same thing. Is this a common issue when using an aftermarket wireless carplay unit? I watched him pair the phone with Bluetooth. Does he possibly need to be doing something else like connecting to wifi?