I'm very new to ableton. When I first open a set I was working on, hitting spacebar behaves the same as pressing option-spacebar. But as soon as I hit stop to rewind the set to the beginning, the behaviour stops.
As an example:
I put the playhead at bar 9 by clicking in an empty part of the arrangement. When I press space, it starts playing from bar 9. Then I hit space, and it stops playing and when I hit space again it starts from bar nine again. Which is what I'm actually used to based on other audio editors.
However, as soon as I hit STOP to rewind to the first bar, then press space, and then hit space to stop again, the next time I press space, regardless of where the playhead is, it will start from the beginning of the set.
If I hit option-space, it will play from the playhead.
Most of the time I'm making minor tweaks to the placement of drum hits, so it's useful for me to not have to always start from the beginning, but just a measure before, and I can't understand why I get that behaviour when I first open a set, but that behaviour stops after I hit STOP the first time (after it rewinds to the beginning.)
I can do a screencast if it helps.
PS I'm using the free trial of Live 9.02