My 2001RB finally arrived yesterday in a nice SKB 4U rack case. I quickly tested it through my 15" cab that I use for band practices and quieter needs. I connect the thing, set it to bridged mode, set the "right level" knob to full (I read the manual several times while waiting for it to arrive to familiarize myself with everything, plus I've been using 700RB II for years prior to that, so I'm not new to GK), plug my speakon cable to my cab, plug it in, and power it up. I noticed as soon as the amp is plugged in, the led power light is green. I turn it on, it blinks red a couple of times and it turns blue. Ok, here we go. I set my eq noonish (more like 11 o clock for starters), set my A channel gain, the boost and start turning the woofer. Nothing, nothing's coming out. I check my connections, all seems to be right. I start cranking the input knob slightly above noon and I start getting a low output distorted tone. So something is coming out. I turn it off, put it in "dual mono mode", and same thing again. Low farty distorted tone only after I crank up the input somewhere above noon. Both A and B (distortion channel) do the same thing. I'm pulling my hair out of course, this simply cannot be happening, just my luck.. Luckily I have an Ashdown head there too, so I test it to see if it's the cab acting out - works fine. I switch back to 2001RB again. I try out all the speakon outputs, and again, same thing. All of this happened in a period of like 5-10 minutes. I let the seller know it's not working. I put the amp in the "bridged" mode again, set it up again, turn it on again and bam. It works. Glorious power and tone. What just happened? Did it have to warm up a bit? I test it for about 10 minutes with 2 of my basses, all good, distortion channel good. I turn it off, try the "dual mono" mode, all good, all speakon outputs good. It works. Ok, I turn if off, pack it up, let the seller know about the weird behavior and luckily, I have band practice later that day, so I'll test it through my GK NEO 412. Band practice arrives, I hook the amp up in a "bridged mode" with my GK speakon cable. Again, nothing... Jeez! Low farty output for about 6-10 minutes (I really should have timed it..). And then it comes to life again. We're all floored by this thing's tone through my 412 and the incredible warmth that it actually produces, seriously haven't expected such a full warm tone, it just shined with my P with flats. Heft, power, low end, everything was there. The distortion channel sounded great too from what I've tried a bit too. Our practice went for about 40 minutes, and it worked without a hitch. Just to test it, I tried turning it off and on again. No problem, tried it 3 times, worked fine. Looks like the "cold start" produces an issue, and I'm not sure what to do. I contacted GK about it, and they asked me if it's problematic after the "cold start" or after every time I turn it on. I let them know about all that happened and they want the serial number too. I left my amp at my drummers to pick it this Saturday for a gig (should have taken it home I know..), along with a backup amp. Any ideas what could cause this thing to act weird for the first 10ish minutes? Relay problems? Capacitors? I didn't smell any burnt smell, and who knows if the seller knew about this or maybe the shipping caused the problem.. I'm not in the USA unfortunately, and I don't know if there are any official GK services in Europe at all, so that's another huge bummer. My guitarist is an excellent amp tech though, and he could check it out. Any help would be appreciated because this thing, when it works, works like a champ!