I have tried putting kz wireless aptx cable modules into headphones (on 32 ohm ones). While it works and sounds great, the battery is just too small. Maybe good for just a couple of hours and that's it. Replacing a bigger battery isn't also guaranteed to help, if the module will just charge for a specific amount of time and will not fully charge it. If you really want I suggest you test it.

Plus, usually you can't connect both gnd/negative of the left and right outs (probably th + side too on these tws). So if you plan to still connect via a trs ended cable, use a trrs jack or balanced connections on the headphones.

On headphones the position of a 2nd driver may be too variable from person to person. For example if it aligned to your ears, you get more treble. For a loud speaker there is also this directional aspect, but most of the time the listener will be far and it won't matter that much at that point.

Iem's can do multiple drivers because they are already positioned in a specific spot in the ears.

You must be very lucky. If it's still in warranty, I'd have that replaced/fixed. If not, just use a dac.

If your dac connected to pc still has the same problem, then that is software issue. Maybe there is still some effects/eq running somewhere.

I'd disable APO or any other audio effects/eq applications first. Then check if the outputs (hardware) are fine or not. Check in sound settings too, the sound device properties, make sure to disable all effects.

Those pc/laptop headphone outs should just work as long as the driver is installed. It's something they figured years ago...

Because games already know how to process audio for stereo output. Heck, even mobile BR games know how to position audio. It's not rocket science as you have just 2 ears.

If tv os is android based, maybe a class compliant audio device will work.

Because it is not tuned for your ears. The best headphones/iem (or the one tuned for your eara) are the ones that sound right the first time you put it on. Same with a speaker. And that's why eq exists to make it sound right to your ears, than your ears trying to adjust to it.

Sinus by Mats/Morgan

• for that bass line
• to check cymbal sounds, maybe also the delicate drumming
• to check everything in between

I've had Bluetooth Haylou and Ugreen that die maybe after 2 years. Either the battery or charging case dies, or the earbud just opens by itself.

For wired, kz decals fades over time. Still works thou.

Haylou W1 - with aptx, warm but just needs a little bit of brightening up with eq. This was previously my daily driver, but have been into wired things lately because of electronic drums.

Kz eda balanced - my current cheapest thou I usually just use this for electronic drumming. Bright, but way better than previous kz zst. Just eq them.

What device are you listening from? Phones usually have settings for mono audio. For example in Android it is in Accessibility settings.