Hi all. I'm having the same issue I've seen others having with my new Quest 2. It used to not be this way, however it has gotten worse after an update around Christmas.
I'm a music producer and am VERY protective of my hearing. I carry two sets of earplugs with me on my keychain just because I never know when I'll end up somewhere loud. I know this isn't an issue with my ears. Ever since this update, using headphones or even the headset regardless of the app used, minimum volume and max volume is hardly even a 3db difference. Occasionally I can mess with the quick menu and the volume will suddenly be louder like it used to be, but no actual fix. I can be in bigscreen, vr chat, alt space, rec room, any app honestly and the volume at Max is literally too low to even hear someone next to you. This is the same with headphones, and its the same without. It's incredibly frustrating that this used to be a non issue, but now it's ruining my experience with my Quest. My girlfriend has another quest 2 and she doesn't have this issue. I also have a Quest 1 and don't have this issue either.
Are there any known fixes? All I know is that others here on reddit are suffering from the same issue.