from 256 to 512, ZynAddSubFX doesn’t start. Oppositely, with the default option, the FluidSynth works intermittently (start once in a while, usually doesn’t).
Anything else (besides the buffer change) should I change in the options to reduce xruns? Thanks!
Regarding FluidSynth, AFAIK, it works perfectly with the default options.
Somebody could confirm the issue with FluidSynth?
Finally, you shouldn’t have XRUNs with FluidSynth. If you have a RBPi3 B+ you should have XRUNs with Pianoteq, specially with Grand Pianos. Also with OBXd and some ZynAddSubFX presets, but not too many.
If you have many XRUNs, probably you have a “power supply” problem. You should consider using a better one. Also put attention to the power cable, as it’s more important that what you would think.