cmt - Delay Line, wrong delay with setting 0

[superpaik]

When using Echo Delay Line, there is a malfunction when:

• dry/wet balance knob set to 1 (full wet)
• delay (ms) knob set to 0
  What I would expect in that case is no delay at all, but a weird 0.18s delay -when using the maximum delay 0.1s version- is produced.
  When the delay knob is increased (>0) then starts to work properly. When arrives at 10, there's a delay of 0.1s, which is correct. Then go back to 0 and the delay is around 0.18 again.
  Similar effect happens with other Echo Delay Line versions (0,01s, 1s, etc.) and also when channels are not linked.
  I checked it with audacity as well, but I attach a screen recording using the free vst "Wave Observer" for convenience.
  It starts with the effect deactivated, and when activated you can see how the sound is produced around 0,18s later. And see how it changes when the delay knob is adjusted.
  
  Tested on lmms 1.2.2 windows 10 64bit

Use case: I use that combination to slightly delay 1 channel to create stereo effect, making a variation from left to right to create panning effect as well.
Work around: when the delay time is set to 0, dry/wet should be set to full dry.

[zonkmachine]

Issue confirmed. Code here: https://github.com/LMMS/cmt/blob/f7c25ed4ef7f4d7efb1bcd4229d25595d4f1ce55/src/delay.cpp

[zonkmachine]

Reported upstream. Error located and fix is on it's way.

[zonkmachine]

Fixed upstream in cmt. LMMS fix Depends on #6151 and LMMS/cmt#3