I did a lot of testing on my Q35 and that is the result. Whenever I am connecting Q35 powered off via normal aux cable, and I tried a few, the sound is muffled and too basy like everyone says. When I am turning them on while wired there is no sound at all.
However when I am using Soundcore inline mic cable which was in the box with headphones, the sound when they are off is again muffled and basy, but when I turn them on this time the sound is on and it sounds like it should, I can use ANC etc. Interestingly when they are on using soundcore cable I can’t turn them off unless I plug out the jack.
Unfortunately when I plug Q35 with soundcore cable to my older flat TVs for retro-gaming purposes, whenever I turn the headphones on the sound again is great, but there is also annoying buzz. I really don’t want to choose between great sound but with buzz when they are wired and on and mediocare at best sound when they are wired and off. I am gutted, cause I absolute love these when using them with bluetooth, but I am out of ideas how to force them to sound good when wired and I will probably refund them. Any ideas?