If you are inside your (possibly very cheap device) playing god already, it may be worthwhile to check and fix the soldering and wiring. Problems like speaker interference, poor Wi-Fi reception and unreasonably frequent freezes can be traced to that.
Typical fixable problems: bad solder joints, wire lints (causing shorts and interference) and Wi-Fi problems.
Wi-Fi Antenna fix
The Wi-Fi antenna in my device was a bit torn, possibly soldered on the wrong places on it and with shorted coax cable too and the PCB connection came right off and left some weird white residue behind on the copper pad (glue or corrosion??).
To correct all that:
- I cut a whole new microstrip antenna from a copper tape (I used this design).
- Cleaned the old coaxial cable and pcb pad (had to use knife) and soldered that back right this time.
- Covered the antenna from both sides with Kapton/polyamid tape and DONE.
I gained about 15 db to the signal and it sure feels more reliable now.