Thanks
Matrix10, but could not see nothing to fix it for VU+ SOLO.
Very rarely I've seen and read so many useful info about a hardware problem!
But clearly, it depends on how much you know about electronics, as Matrix said.
Summarising, these kind of problems depend, 99% of times, either on the capacitors or on the power supply. There isn't much more to say.
If you are not a technician (and surely you aren't) look for one and let he get your box fixed.