POTS voice quality is pretty minimal (8 kHz, 8 bit, one channel). I wouldn't be surprised if a model would struggle more to isolate a speaker there vs. a higher

POTS voice quality is pretty minimal (8 kHz, 8 bit, one channel). I wouldn't be surprised if a model would struggle more to isolate a speaker there vs. a higher fidelity audio channel. Then again, local noise reduction on modern phones/earbuds probably goes a long way to avoiding that problem.