Fender Hot Rod DeVille - voulme fluctuation issue

[tremoloman***]

I've noticed recently the volume on my Fender Hot Rod DeVille seems to fluctuate a bit now and then, especially within the first 10-15 minutes of use. Any idea what could be causing this? My guess is a tube may be dying, but the amp is only a year old. Is there any way to test the tubes? I'd hate to drop some serious coin on tubes and not even need them.

[6STRINGS 9LIVES]

Hey Trem.. could be power tubes , try putting some contact cleaner on the pins and giving them a gentle scrub with a tooth brush , push the pins in and out a few times in their sockets , is the drop off there in all three channels ,if not then it could well be a pre amp tube the deville has 3 12ax7's does it not , any different smell eminating from the amp , , ahh the joys of tube amps , by the way Trem , are the original groove tube 6l6's still in there .. i seen those fail early before .. 6S9L

[Spudman***]

Another thing to watch out for on the Hot Rod amps is the input jacks. They have a tendency to break at the solder joint just under the faceplate. I know the Deluxe has pc board mounted jacks which can be problematic.
When it starts fading try wiggleing the cord at the jack or move the cord to another jack and see if the problem persists.