Currently experiencing intermittent problems with the PCM display, sometimes it works others it doesn't. Radio and CD function normal, sounds and search also ok apart from visually.

So the last week or so I've have a black/blank screen with normal function the I start it up 2 days ago and the display was back working. Started the car today and the porsche logo appeared the went blank again. 20 mile round trip came home switched engine off, turne radio off then back on and the porsche logo w/ white back ground appeared then cut to blank screen again....any ideas? Thought maybe connection issue but pushing double din unit has no effect. Checked fuse box and all ok too