Things to check on the power main: Ground, voltage, heavy duty power cord
Things to check in the power supply: fuse, tubes, tube caps, loose wiring, contact cleaner
Did you try Dexoit on the tube caps? I used it on all electrical connectors, tube pins, etc.
http://store.caig.com/s.nl/sc.2/category.188/.f
I use a cotton swab (Q-Tip) to apply the 5% solution that cleans and protects the contact.
OK thanks I will check all this and ultimately but 2 new tubes.
I have not tried Dexoit, but... my EC445 is brand new, so the contacts should be clean and oxyde free ?