Static or line voltage instability

Hi,

Maybe some of you guys enlighten me on this subject. A few weeks ago, my CJ preamp suddenly stopped playing in the the middle of a listening session. A volume level of "0" appeared on the led display like it put itself on mute. Since I could not make it switch off mute, I closed and powered it on again and everything came back to normal. I could not see what could have happened even double checked if the unit and the whole system was correctly plugged in the wall suckets. All showed OK.

Last weekend, the same thing happened, even after multiple listening sessions since the first incident. But this time, my power amp blew out all its fuses and the preamp stopped. After replacing the fuses in the amp, I've tried to power the preamp but it will not play. Even the tubes do not glow. So something is wrong, at least with the preamp. A CJ technician told me by phone that my lines could be having problems. I've had dedicated lines for my system for the last 15 years and never had any problems since. I'm a bit confused.

Any ideas ?

Thanks !