I agree with Buffalo Jeff, if its happening on a regular basis that can't be right. I had a similar problem a few months back with my V+, CS sent out an engineer who came to the conclusion that my box was "knackered"
he replaced it there and then.
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If you are in danger of being overrun call in the Frogstamper
Rimmer: OK, step up to red alert.
Kryton: Are you sure sir? it does mean changing the bulb