Static from Speaker on Krell KAV 250 Power Amp

I noticed a static/distorted sound coming from my left speaker and thought the tubes on my ARC LS-15 were going. I bought new tubes from Upscale Audio but the static sound was still coming from the left speaker. I hooked up a different speaker and the static sound was still there. My guess there is a problem with the left speaker terminal on the Krell KAV 250. Anyone with similar problems? Suggested fix? Thanks.
Krell has an EXCELLENT reputation for service of their products. I suggest contacting them.
Yes Key metric, I did contact Krell via email and about 20 minutes after I sent the email, Steven from Krell called me. Talk about great customer service! He suggested I try a few fixes before sending the amp to Krell for service. Turns out my balanced interconects were not fully seated. I reattached them and the system sounds great. Funny how the no-cost fixes we often overlook. Thanks Steven and Krell!