Yes it seems to be a bug.
No, we do not have a fix. Posting about it will likely not get a fix produced faster either. The fact is that everyone who's "on the project" is too busy with a regular job to work on Aegisub.
There is a possibility the problem may actually be an incompatibility between wxWidgets and recent macOS versions, and that simply rebuilding the current Aegisub code with a newer wxWidgets (where the bug is hopefully fixed) would rid the problem. I did read the relevant code in Aegisub for these sliders a few days ago, and I don't see anything obviously problematic, apart from some of them being set to have inverted value scale.
If anyone has a Mac, can reproduce the bug with the Aegisub version available for download, and knows how to set up a build environment for Aegisub on macOS, a test of whether a newer wxWidgets version solves the problem would be appreciated.
Do not PM me asking for help with Aegisub, Automation, karaoke or anything like that, I won't reply.
Ask your questions in the public forums. Use the Search function, somebody probably asked the same question before.
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