Help Loud pop when muting BAT VK-3i preamp


Hey guys! I just got a BAT VK-3i installed in my work-in-progress listening room. I had the guy still in the box for a few days, but wanted to wait until I got my dedicated lines installed to fire her up.

NOW...

There seems to be one small problem with the mute function. Whenever I press mute on either the remote or the front panel of the unit, I hear a very loud "pop!" from the left speaker (Magnepan MMG), primarily (maybe there is something in the right speaker, but I cannot hear it over the very loud pop in the right speaker). Also, when I turn the volume down to "00" I get the pop (because the muting is engaged) and when I power the unit on, after the tube heath 60sec check-up/delay I get the pop again. Now, I've rotated out my amplifier, my speakers, the interconnect between the amp and preamp and I had the "pop!" with every iteration. Also, it does this even if no source is playing (or even turned on) and also even if I select a source via the knob that I have nothing hooked up to. Therefore, it cannot be the source or anything upstream of the preamp. The only thing I haven't changed is the speaker wire (Kimber 4PR). I am going to put my old preamp back inline today and I expect that the pop will go away. Do you think this could be a bad tube? I figured I should probably talk with BAT on Monday, but I just got finished e-mailing this to the seller here on Audiogon and I wanted to post a similar reply to the forum to see if anyone might be able to help.

Thanks!
-Marc
mre2007
Interesting... I just purchased a VK-5i here on Audiogon, and I have the same problem. I had another problem in addition, so sent the unit to BAT to look at. I wonder if it's a common problem with all their older preamps.

- Stew
Smeyers: Would you mind contacting me after you get the diagnosis from BAT? It could save the preamp a trip if it ends up just being tubes.

I'd really appreciate it!

Any other ideas?
Could be a DC discharge. BAT preamps have been known to do this. It goes right on thru the system to the speaker. Give BAT a call.