Fender Blues Deluxe Problems

[photoguy11579]

I have a Fender Blues Deluxe tweed amp - original from the mid-90s, not the reissue. I've had it since the mid-90s and have never had any issues with it.

Now it doesn't work very well. Randomly when playing, it'll stop producing sound. First I thought it was a bad cable, but the cables were fine. I noticed that when the sound stopped, it would turn on the drive channel automatically and no sound. If the drive channel is already on, it just stops producing sound.

Any thoughts on what's going on?

Many thanks!