Audible Illusions Modulus 3A problems

I own a pair of AI L-1s. They both have a master volume control in addition to seperate volume controls for the left and right channels. One was manufactured in 1994 and the other in '95. Each pre-amp has a sound that I would describe as a static pop which comes from the loudspeaker. This fault only appears in the left channell volume attenuator of each unit and the '94 unit has the problem to a much greater degree than the '95. I get no such static pop from the right volume control or the master volume control,which may be coincidental. I posted this concern on this forum about a year ago and got a response which suggested rubbing alcohol applied to the volume attenuator with an eye dropper and it did in fact eliminate the problem,but only for a couple of weeks and the problem resumed...no better... no worse.. I also received a post from Jerry at AI asking that I call him as soon as possible as he might have a solution. This was very encouraging and I appreciated Jerry's concern, but when I phoned Jerry, I got Art. Art stated ,under no uncertain terms, that he had never heard of this problem before. The conversation did not go very well and I still have the problem. If the volume is not being adjusted then there is no noise... so I live with it as I thoroughly enjoy the sound of the pre-amp but wish there was an easy fix for the static pop.
This may not be of any help except to let you what to expect from AI and that there are others with the same frustration.

Regards & good luck!
John

Johnatmc99,
I have a 1995 AI L-1 and it is as quiet as a church mouse. Maybe just defective units or a very uncommon amount of dust in the environment. AS far as the original post i would just give Jerry a call.

Jo, are you sure your amp is working properly? I found some of these 'pops' using the M3A on amps with some problems on the output stage. It could also be a stepped attenuator problem, but this is my experience. The problem was not the preamp but the amp.
Bye

I am sure it is the stepped attenuator. I have switched tons of amps into the system just to have fun
and the preamp, right channel, is consistently the culprit. It is a very loud and destructive sounding pop! The cleaning worked temporarily as mentioned by others.

I do love this preamp and after five years I retain the
original tubes. I've bought others brands to play with but the microphonics were horrible and am going to have to bite
the bullet and spend $100+ at AI or Kevin Deals to retube this.

I am hesitant to do all of this because I pre-paid for the preamp factory direct via my employeement and it took AI a year to deliver and at times I wasn't sure if it would ever show up.

I had exactly the same problem..changed out the tubes and the noise drastically was reduced...only problem is this Pre eats up tubes fairly quickly!