I have recently started losing power to my stereo, it does happen all of the time, it can all of a sudden go off or come on as I'm driving, sometimes doesn't come on at all and some times stays on for all of my journey?? It has cut out twice when I have knocked the key with my knee so I'm not sure if it could be related some how?
You have what we pompous people call an intermittent vibration induced open circuit.
All people here can do is guess the cause of it.
You might get the stereo playing and gently tap around with the handle of a wooden spoon to see if you can induce the fault - before - behind - between - above - below
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