lolFor me I just use the forced High Impedance mod, which changes the parameters in mixer_paths.xml. After doing the mod, it pretty much outputs much higher volume. You have to be rooted to do the mod though.
Honestly still loving my V30. I'm running Havoc OS on it and the DAC works like an absolute charm.
If you want a real upgrade try a dedicated DAC/AMP, for example I have a Schiit Asgard 3 with a 4490 module built in and it is wayyyyyy better than my LG V50 in any mode it can produce.I had two iBasso DX160's. One was the best sounding DAP I'd heard, the other good, but Bluetooth was completely 'donald ducked' on both. Both a little better sounding than the LG V30....but the V30 did hold it's own in many ways. The LG V30 is better than the Hiby R6. The V30 was thought out and was ahead of it's time. I got it 'cheap as chips' on ebay, brand new. For streaming music it is perfect, and Bluetooth LDAC after updating with Android 9....is great with the Radsone ES100. I'm a happy chappy. If anyone can get the V30 very cheaply on Ebay, it's a good DAP.