Reply to Making a mashup, need some help!

Hello guys

I'm currently trying to make a mashup using ableton, i'm not very familiar with it, i used to play around with it like 4 months ago and now i'm back on it, trying to make something good.

My problem here is that the acapella i'm using goes way to fast for the track, if i set the master tempo to the bpm of the track i'm using the acapella won't sound good at all... I want the acapella to go slower but not sounding like it's glitching, how do i get this in ableton?