But surely one would expect that due to the mismatched waves - it's what happens when you make a bad cut where the waveforms don't match - or when you get dropouts.

The looping page in the Manuela tells you to avoid this:
https://alphamanual.audacityteam.org/man/Tutorial_-_Looping

Surely we want users to hear if they have a bad start/end to their loop  - otherwise if we smooth it out for then with fades or some-such they will just repeat the audio to make the looping - and then they will get clicks at this junction.

I think this is expected behavior and is NOTABUG

Marked as enhancement.

It's a nice-to-have to have a smart way of automatically repairing the 'join' if the samples don't actually match up.  Possibly there will be configuration parameters in preferences to set how readily/strongly we repair.

So long as there is only one click when the ends don't match, and no clicks when the ends do match, then I agree with Peter that this is not a bug.
On Linux I observe this to be correct.

To demonstrate a "perfect" loop:
1) Generate a sine tone, frequency 441 Hz
2) Enable snapping to seconds
3) Select 2 seconds
4) Loop play.

With a sample rate of 44100 Hz, there are exactly 100 samples per cycle, and exactly 441 cycles per second, so the loop should be perfect (no click).

(In fact there should be no click for any integer frequency sine tone with a length of 2 seconds, but you have to be careful to select to exactly seconds, and not to sample positions.)


I also agree with James that "a smart way of automatically repairing the 'join' if the samples don't actually match up" would be a "nice to have", though I think this would have to support copying and exporting the "repaired" selection, and not only "loop play", otherwise what you hear will not be what you get. (I'm thinking of "looping" use cases).

CLOSED NOT-A-BUG.  It's a feature request.