fazi

I have A6 3.0 DTI Avante 2011. Last week I noticed for first time a message on my dash board.."Key weak battery". After that the MMI displayed started having mind of its own, coming on and off when it wanted. I changed Key battery but the issues continues. MMI on and off and comes out when it wants, sometimes it goes blank screen and still out and then goes in. On initial starting the engine again comes out with display screen working properly, sometimes it does not. Any ideas?