Help with Aegisoft audio zoom slider not working on MacBook

[Ultimathor]

Hi,
I have an annoying problem, that I hope that someone can help me with. I've been working with Aegisub on my 27" iMac and that worked fine. Now, I'm trying to use my 12" MacBook and the audio sliders don't seem to work properly. This means that I can't highlight the part of the audiostream that I want to subtitle.

As you can see in the attached file "Aegisub audio zoom high", the sliders look weird. Also, it's not possible to move them up and down. That means that I can only select to different audio zoom levels:

- The high zoom that you can see in the "Aegisub audio zoom high" file where the width of the audio window is about 1 second in total.
- The low zoom that you can see in the "Aegisub audio zoom low" file where the width of the audio window is about 24 minutes in total.

Both of these two settings are really unpractical to work with. I am therefore hoping that someone can help me out and suggest another way to change the audio zoom level.

Thanks in advance.