+/- 5 BPM was a biggggggg difference back in the vinyl days LOL.
Keylock is not based on master or anything. It just means that when you change the speed/pitch of a track the musical key it is in won’t change. Keeping the key the same while changing the speed takes its toll on the hard- and software. The bigger the speed change the harder the work is that needs to be done. Although both hardware and software are getting better at it, in some combinations you can hear the sound quality deteriorate as the key lock has to wrok harder and harder.
The only reason to take of the keylock would be if you want to change the key as well. At +/- 5 BPM this is clearly audible, but might provide a desired effect.
Greetinx.
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