No audio play back in Cubase Elements 9

Today I opened my project and the audio tracks will not play. The Groove Agent tracks play but incorrectly and not where shown on the track. I am pretty amateur so i wonder if I’ve done something wrong. I opened other projects and they don’t play audio either. When i use the ‘play’ tool they play fine. When I turn on the click (tempo) track the tempo changes from 145 bpm (project tempo) to 120 bpm and the click doesn’t sound and gaps appear between segments. I have been trying to learn some automation on this project but it still won’t come on if i turn the 'read’s off.Everything was fine when i turned it off yesterday. My interface is presonus firestudio and my computer is Windows10.

I also tried to add an audio track and tried to record on it. I got an error message saying ‘too many tracks recording’ when there was only going to be one track recording.

Fixed it all by myself! I tried listening without the firestudio project interface, just using the sound card in the computer and everything played. So I figured it was the firestudio. I downloaded updated drivers for the firestudio and voila; everything is working again, PTL.

Good evening guys, please help me how I change the tempo of the audio in a cubase trek LE AI ELEMENTS 9