Have a Tweaker 40 head for about 1.5 yrs. Never gigged with it, always kept in my music room at home, played at moderate volumes only. Well yesterday morning it just stopped working. Was playing thru it, put it on standby and "Click", no lights or power. Checked fuse and power cable, all fine. Luckily still under extended warranty from GC. Dropped it back off at GC, they said they will handle the repair. Will let you know what transpires.