I just powered up my Legacy and the Dirty channel doesn't work, by which I mean neither the footswitch or button change over to the dirty channel. Also, I've found recently that when I take my amp off standby after letting it warm up a few minutes, the signal is very quiet and crackles loudly when I play hard for a few seconds, then is okay. This happens no matter how long I let it warm up for.
I had to reinstall the tubes when I got the amp (which I've never really done) so do you think its a problem with this? the channel worked fine before..

so regardless of what you do the amp stays on the clean channel?

i would say there is a problem with either the channel change switch or the footswitch jack on the back.

the other problem is perfectly normal.
when on standby voltage is only applied the the heaters for the valves,there is no ht voltage so when you take the amp off standby voltage is applied to the power supply/capacitors which takes a short while for the amp to come to life and will start off very quiet possibly with noise as well.

Ah cool! Thats fine then!

I thought it was the footswitch tol, but the reverb/loop still turns on and off so it cant be. As I said I did reinstall the tubes (never done that before) and maybe one isnt in quite right or something.. Ill give them a wiggle around.

It occoured as I was starting to plug my pedals in, I took the amp off standby to try the dirty channel w/ds1 thing and nothing happened, it just stayed on the clean.. Never seen that before!

sell it and buy a new amp

It could be faulty tubes as I believe certain tubes run certain channels.

When you said you 'reinstalled' the tubes did you replace them with new ones? Valve amps should be retubed at least every few years.