Is it the tube pre or the rca/xlr adapter?

What tubes are inside the preamp? You are listening to the tubes as well as the preamp. Don't assume the preamp is performing its best.

The BAT adaptors are better than many others on the market but I found they degrade the sound in comparison to using balanced cables. The BAT pre also needs to warm up for at least a half hour before serious listening. You might want to burn in your system with that few hours it would probably sound better after some significant playing time.

Hope you solve your channel problem.

After you get that fixed, you need to break in your equipment, especialy the BAT stuff for another 300 hours. At least. This stuff takes a lifetime to break in. I had a VK30se & it took a long time and the change for me was significant.

Try calling BAT. They were very helpful with me.

Good luck.

Thanks for the suggestions! I do like the overall sound that I am getting. Cymbol rolls are crisp and you can really hear them ring. The LF is not what I am used to from a solid pre, but I don't need to hear the foundation vibrate. Imaging is much more pronounced and deeper now. Before my mishap last night I was trying to put my finger on just what it was that I wasn't hearing. I was listening to Aja and it seemed that most of the consonants weren't there. So I guess the detail I think I'm missing is in the mid-range frequencies. Based on some of your comments I'll give everything some more time to burn in. I haven't popped the hood and checked which tubes are installed. I assumed they are the BAT 6H30's since the unit is almost new. I will double check. I failed to mention before but I'm connecting the Classe with a 1M pair of Quattro Fils. Yeah, I have replaced the whole mid-section of my system all at once and now I realize that I probably should give it some time.

Twl, my TT is a MMF 7 and the previous owner mounted a Shure v15vxmr. I can't remember the specs right off hand but I think it matched well enough with the 834P's load. I checked some of Thorsten's posts on the Asylum and found that he recommended that the 834 drive 100KOhms or higher. The BAT input is right at 100K. What gets me is that this analog front end seemed very revealing on my old solid pre, that's what led to my first post. I do realize, however, that I am now trying to play at a much higher level quality wise with equipment that is not as forgiving if there are weak links in the system.

I have sent Roy an email about getting a new wiring harness. I don't know if that will solve the recurring channel loss problem, but it will sure solve the channel loss I have now!

Is there bypass input in your preamp?
I'd recommend to use no preamp in your case. EAR834P has a volume controll so why'd you need another one?
If you talk to BAT, Viktor may implement for you an upgrade for having pass-through (passive) input.