Just tripped over this one yesterday. I'm using the Pulse waveform from Osc 3, with mod set to 0, to get a nice clean square wave. (Doesn't seem to be possible with the analog oscillators.) However, on the note A0, with octave set to -1.. I get nothing but a click. See attached video. I did not investigate fully but it also seems to happen on sine and triangle waves at that pitch.
Known bug? Workaround? (I've transposed the song by a semitone, which is not my preferred fix.) TIA.