HI Bakis
 > the exact same happens to one of my two doepfer
 > vu-meters lights too!
 > I just tap the plastic screen a bit and the LIGHT
 > TURNS ON AGAIN.
 > ALTHOUGH, for the last months, I didn't have any
 > problems at all with this light.
The light bulbs in voltmeter are steady point of failure. Since my first
 cassette deck in 1974 all lightbulbs in the meters of each piece of
 gear I own failed. This is because they basically overheat: the bulb is
 held by a very narrow rubber gaiter, which shall prevent that the light
 comes to the rearside. But this rubber gaiter makes the socket end of
 the glassbody to be overheated, while the head can cool. This causes
 micro breaks in the glass body, through which oxigen can enter the bulbs
 body and in consequence the filament will burn away.
 They only chance is to replace the light bulbs by ultra bright LEDs.
 Florian