PRIMA LUNA DIALOGUE PREMIUM - 20 minutes and then loud pop and buzzing in 1 channel

  @mickeyb

Sell it now. Seems everyone else is. You see how many are for sale?

Yeah, check out the prices. If you find a good one it's only $1000-$1500 below list. Most used equipment goes for 50% or less. The Dialogue Premium series has been superseded by their new EVO series of balanced amps, I notice that many have just gone up for sale. I'd sell mine at $1000 off so I could buy the new ones. That's a good deal for me!

Have you talked to the person who sold it to you? They may be of some help or stand behind their sale and assist in it's repair.

Rollin

Troll post. Why wouldn't the OP just contact the seller.

+1 Check the switch on the right side for tube type. FWIW my PL Dialogue Premium has been absolutely bullet proof for three years I’ve owned it..
best
k

vespacraig65-

Since you've switched EVERY tube, then you may have eliminated the possiblilty

Call Upscale to get a referral for a shop to repair it
The suggestion of the switch on the right side will have nothing to do the problem. The amp will work fine in either position.

New development- John at Upscale told me to fire up the amp, not connected to the preamp. Let it pop and buzz and then wiggle the small tubes. As I was about to do this, the buzzing then came out of the LEFT channel. Prior to this is was always the RIGHT channel. This gives me hope. So I will purchase 6,   12au7 tubes ASAP and see if this fixes the issue.  I am just hoping I don't have to ship it to California from Boston. John , the tech @ Upscale said 30% of the (tube) equipment he gets to repair DOES NOT NEED REPAIR ! That fact inspires me to try more trouble shooting on my own.  Hence purchasing brand new 12au7's. 
thanks everyone for your suggestions. I'm new to the Audiogon community and very impressed with other's concern for my issue.