38% of 61 verified Onkyo TX-NR6100owners don't recommend it, and 2 describe specific problems — based on real owner comments from Reddit, enthusiast forums, and YouTube.
For balance: 44% recommend it. This page collects the complaints so you know what you're signing up for — read the full owner report for both sides. How we score
“Bought a new one (TX-NR6100 practically identical some people refer to yours as the “Costco” variant)and had nothing but issues (HDMI signal appearing the same as your 2nd picture and complete loss of signal) Returned for a replacement and the 2nd one did the exact same.”— EqualPositive8766 on Reddit
“My center channel (Elac unifi 2.0 uc52) literally came to life, maybe that one was a little bit power hungry with the Onkyo but the Yamaha Aventage receiver completely unveiled the s”— _waistland_ on Reddit
“I had the NR6100 and it was nothing but problems. I'd turn it off at night only to turn it on in the morning to no sound. I would have to go through the whole set-up process for the receiver to work.”— Responsible-Golf-583 on Reddit
“TS has no idea why zone 2 won’t produce sound and all audio continues to go through FR and FL. I returned the POS and am going back to my 12+ yo Sony STR-DE597!”— Seawench41 on Reddit
“the NR6100 I had was fine for music but abysmal for movies. I guess to each their own, but I don’t think I’ll ever buy an Onkyo again.”— Ark_Onyx on Reddit
“When I routed everything through the receiver, I got an error message that the receiver's onscreen menu was not supported, and the screen would blink on and off.”— DamageMcRamage on AVS Forum
“I'm going to give the 6100 a couple more days, see if I can figure something out but I think I'll probably be going back to the "old girlfriend."”— grafixfreak on AVS Forum
“My 20yr old Harmon Kardon AVR 630 has a much better adjustment range and seems way louder and cleaner than this Receiver at less watts.”— AirborneB on The Klipsch Audio Community
“I found the same issue but only with the non 4k movies where in times the music may be so loud I can't hear the dialogue.”— kepenach on Reddit
“When using the cable TV box and I change the channel, I get a popping sound out of the front right speaker.”— anonymous on AVS Forum
“I upgraded to an Onkyo TX-NR6100 from an Onkyo HT-RC180 and I am more and more regretting the purchase.”— anonymous on AVS Forum
“Been running the XLS's by themselves on this Onkyo so far. It's OK, but nothing great.”— DonFroelichJr on Audioholics Home Theater Forums
Not complaints — practical notes from owners that didn't affect the score.
“seems to do very well for sound, but agree on lower volume settings it is a bit muffled. anywhere from 35-40 and up is fine.”— exiteternium on AVS Forum