i have an idea that i believe might work?
An equalizer in android. i know its not supported in the android api but it seems plausible to create a program with different audiofilter.csv audiopara4.csv audiopreprocess.csv files that would be swapped with the default ones in the /etc folder. i have edited to these files already and its not difficult to edit them. i actually switch them often with some pre-made ones like a "powerful" one and a "Bass" one.
any ideas if this could possibly work for root users?
im not a dev but i have experience in writing in C++ not linux lol.