Aesthetix Io won't start...


I have had no problems with my phono preamp until yesterday, and like it a lot. Yesterday it stopped working. With the Io, the normal operation is that when you turn it on (on the power supply), there is a Heater light that goes on immediately, and then a High voltage light next to it, that goes on after a few minutes. Now, however, the High voltage light stays off, and there is no sound. I have tried waiting for an hour, changing the power cable, checking the fuses, and even changing all the tubes both in the power supply and in the main unit. But it did not help. Any ideas?
Ag insider logo xs@2xo_holter
Problem solved, thanks to Rushton's advice! It was the Buss fuse that was gone. Great to get help like this.
Great to hear, O_holter!! BTW, Jim says not to worry about anything being wrong if these fuses blow. Just replace them and move on, they are unlikely go out again and it's not an indication of a problem with the unit. This is why he's eliminated them from current production.
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Great to get this kind of help in a forum. Perhaps Aesthetix users could help make a troubleshooting list. for example, how long before reconnecting the power cables, how to search for tube errors, how to replace fuses. Silly me, I didn't catch up to the fact that I was hearing a typical fuse error (no sound) rather than tube error ( bad sound) and used some hours changing tubes. Eventually, I replaced the bad "Buss"-marked fuse with a standard gas station 5 ampere fuse, and have not noticed anything wrong afterwards.
I have developed the same problem-heater light is on but high voltage light is off and there is no sound.

The external fuses check OK (replaced). I cannot see an internal fuse although the manual alludes to two such fuses. This is the Signature version. Any suggestions would be welcome.