Krell S300i Volume Control Popping Noise

Recently purchased from a dealer, adjusting the volume control up or down makes a popping noise through the tweeter, which I can hear even with music playing. The dealer swapped for a different unit, which still pops, but not all the time. The old unit popped all the time. Not only is the pop annoying, it's a borderline concern for tweeter safety. I called Krell, long story short, was told that, yes, it pops. Speakers are JMlab Electra 915.1, and other equipment includes Musical Fidelity A308cr pre, power, and CD player, and Oppo BDP-83. Interconnects are Cardas, speaker wire is homemade, but also subbed in Monster Cable to no avail. In addition, I get more tweeter hiss with the Krell than through the Musical Fidelity gear. These quirks are not commensurate with my idea of a high-end product. I previously owned a Krell KAV 300iL, and do not recall having this issue. Thanks in advance.
had an s300i for about 6 months. never had any popping/noise when adjusting the volume. how's your power supply?. i ran dedicated lines and high grade pc's. that's the only thing i can think of since you've already tried another unit.

i enjoyed the krell. good luck getting it figured out.

Return it and get your money back.
Thanks. I suppose it could the the power line. I'd have to try another location to verify. I was told early production units had a loose ground, and wondered whether that could impact the volume. A UK forum contributor found the same issue, calling it a clicking, rather than a popping, sound (but I have no transformer hum, as he reports).

The Krell integrated was noisy in operation, it seemed to use the same numeric volume control as my Arcam pre, but with an audible click with every change and it hissed through the speakers worse than a Naim pre, plus there was a very noticeable mechanical hum
I have the same noise.
But i dont have waranty.