Modify input speed of additional actions?

I'm a video editor and one feature that I hate in QT is the inability to playback a video at 2x speed with audio, something I need to do a lot to review videos for QC. The next best thing is to hit Opt+L 9 times to get playback with audio at 1.9x. As you can imagine, though, hitting Opt+L 9x is annoying and unworkable, especially if you have to stop a lot to shuttle backwards and forwards. So I was hoping I could fix this with BTT.

Here's what I did:

Made a button called 1.9x that triggers the keyboard action Opt+L

Attached 8 additional actions that were all also Opt+L

Here's what happens: playback speed dances around. It sometimes goes to 1.8x, sometimes 1.2x, sometimes 2x. It's entirely inconsistent. I wonder if it's because additional actions triggers all at once, confusing the sysytem. Is it possible to include an additional action that is essentially a time delay? Say 0.1 seconds or something to that effect?

I think you could just add (delay 0.5) or even less, before or after each additional action runs. I do this in a script that has to execute multiple actions within the preferences pane.

ex: