Android seems to perform better than PC

[LunaMoo]

Many people complain about input lag of PPSSPP, that being said they never make it an platform specific issue and there's also the thing that most other people can play such rhytm based games just fine, so it's very possible it's something on some systems/hardware which makes that problem an actually bothersome issue.

Maybe you just don't have enough RGB lighting(;p).
You could also be using settings on pc that makes it much worse like cpu based texture scaling, which should NEVER be used in games that require smooth animations since it ruins frame time even when not affecting average fps.
Display also matters a lot, many people with even more powerful gaming pc's have awful monitors or tv's which could also be a huge factor:]. Same for driver hacks, many people think they're being smarter and abuse graphics drivers settings to enforce things over applications and this can be pretty awful actually.

Don't think BT speakers would be any factor as I use sony's BT headphones without any noticeable delays vs cable myself.