I have the GEX P920XM tuner and F700, whenever I start my car it defaults to channel 0. Does anyone know how to make it default to the last channel I was on when I turned off the car? Thanks!

You have it powered (wired) up wrong. If you use the IP BUS, you only need one of the two leads connected to power...and it must be to a constant 12V...not a switched. You more than likely have it to a switched power supply so it loses it's 'memory' every time you turn the key off. Read your instructions carefully. Either the red or yellow doesn't get attached when using the BUS.

03Aviator thanks for the reply, I'll look at the wiring