I have a 2007 Land Rover LR3 V8 SE. The engine was recently replaced due to the last one having a broken connecting rod. It runs perfectly fine now.
But for some reason the radio keeps turning off at random times, while I'm driving or while I'm sitting with the car off (but still with the key half turned).
Sometimes it won't even come on in the first place when I start the car.. other times it turns on after driving for a few minutes, other times not.
When the radio turns off it shows no signs of power whatsoever, no time or any display. All it shows is the lighting around the ***** and disc player when the headlights are turned on. I've already swapped the fuse multiple times, and none of those times have the fuses even looked burnt. I've inspected the amp under the passenger seat, re-seated the cables on it, to no avail. Also pulled the radio out and checked the connections on the back for corrosion etc..all looked completely normal.
Does anyone have any suggestions on what to do next?

 

Pull the radio and check the ground... bet it's not tightened.