[Avulon]

I very much doubt that it's a fault of the headunit which is only really a dumb terminal. From the way you describe the faults it looks like a wiring problem, Poor earth or bad connection somewhere in the highline wiring. Also possible that there's a fault with the satnav unit. Turning it off with the ignition isn't the best idea as it has it's own shutdown process which it should be allowed to follow. For a start, try disconnecting the sat-nav drive. Random battery drains are often due to a fault in the sat-nav not shutting down fully (even though the led does still go off in some cases).



Whenever you make a change to the system like adding or removing devices you need to switch it on and let it sort itself out - give it a minute for safety. then off and back on again. If it is the sat-nav drive causing all the problems you'll be rewarded with a slightly less attractive display - but it keeps working - no sat-nav though.




If you really find it worth trying a different display unit - pick up a 2nd hand one for a lot less than £139.99! I've got a spare here I'm happy to sell if wanted.