Effects section slider values will incorrectly change when left-clicked (without movement)

[gonk23]

Bug Description: Surge XT VST3 effects section slider values will incorrectly change when left-clicked (without movement). The standalone version of Surge XT on the same computer doesn't appear to have this issue. Problem observed on both Windows and macOS.

Surge XT Version

• Version: 1.3.1.4b53827
• Plugin Type: VST3
• Bitness: 64-bit

Reproduction Steps:

• Load Ableton Live 11 or 12 Lite
• Load Plug-Ins > VST3 > Surge Synth Team > Surge XT
• In Surge XT effects section, click any empty box
• Select Delay > Dreamy (for example)
• Input > Channel will initially be in the middle, and the hover-over tooltip correctly says "0.00 % (Stereo)"
• Now left click Input > Channel slider without moving it. Tooltip incorrectly changes to "-100.00 % (Left)" even though it's still in the centre.
• Click on a different empty box in effects section, then back again.
• You'll notice the Input > Channel slider is now far left.
• It'll also happen to other sliders, although it tends to go away after a while. (Update: It's only the sliders in the "FX INPUT" section that seem to be affected.)

Expected Behavior: The slider values should not change when left clicking on them without movement. The slider value should correspond to its position.

Computer Information (please complete the following!):

• OS: Windows 10 Home (22H2 19045.4291 64-bit)
• OS: macOS Ventura 13.6.6
• Host: Ableton Live 11/12 Lite, versions 11.3.22 and 12.0.2

[baconpaul]

I wonder if this is live sending us automation we don’t expect. Is surge in a latch mode in live or some such when you do this? Do you see it in any other environment (if you have one)?

[gonk23]

I'm not aware of any type of latch mode being activated. It's immediately after loading Live.

I tried all the other sliders in the synth and they seem fine. It's only the sliders in the "FX INPUT" section that have this weird behaviour.

On Windows, I've just tried Hermann Sieb's VSTHost (1.57 64-bit) and Reaper (7.15 64-bit), and they don't seem to have this problem, so it's looking like it's a Live specific problem at the moment.

Back in Live, I tried TAL-NoiseMaker and Dexed VST3 plugins and their knobs/sliders don't show any weird behaviour.

[baconpaul]

Thank you for the accurate report at least!

We will try and look and replicate!

[gonk23]

Thanks for looking at it Paul.

It's obviously not really a problem in practice because one tends to only click on a slider when they want to change it anyway.