The speaker started making crackling noises and was working intermittently until it finally died.
The tip of the pentalobe screwdriver was too small and would not engage. Had to file the tip down. The plastic opening tools are pretty much single use.
Definitely use the replacement phillips screws. If the screwdriver does not firmly engage, don't keep turning or you'll round the head. File down the tip to be higher on the taper. It should only take a light touch to turn the screws.