Recently started using ableton, not quite sure how alot of it works yet. Loaded up a mix id been putting together, and for some reason it now plays ridiculously fast, at a new tempo. Sometimes when i start up it plays slower aswell. Weirdly though, it plays at the proper original tempo when i export it as an mp3. Is there anyway to fix this? I dont think i set a master tempo at the start, but it worked at the correct speed for a week or so before this started happening. Only reason i can think of it happening was i did a system update, but it was only a few minor OS and flash updates.