I’ve seen some talk about the PWM fixes…but not sure who may have tried them already.
The Yusynth steiner filter is a pretty easy starting point with his designs. Low cost easy to source parts (a rotary switch is the trickiest thing to find) you do have to match two transistors though…which is another excuse to do a really simple DIY PCB:
It’s easy enough to do on a breadboard…but if you’re looking for a simple PCB to test etching with that’s one that’s super simple and useful for building multiple modules later.