Holding down sync for instant double causes temporary BPM change

I use the sync button holding down for instant doubles to clone both decks often to remix a song. Sometimes when I do this it causes a temporary BPM change for a few seconds till it returns back to normal. It can either slow it down or speed it up. Is there any reason why it is doing this and can it be fixed?

Does the deck you are loading the double onto already have a track loaded, or is it blank?

Yes it will always have another truck on it as I’m mixing from one deck to the other when I do clone mixing.

I don’t have a Prime 4 to test, but just out of curiosity, try loading the instant double to an unused channel and see if the problem remains …

That’s kind of hard to test as there’s no eject button once the song is loaded. So you could only test it a few times before you have to turn the unit off and on again. But even if that would correct the problem that’s not an option for me as Deck 3 and 4 I use as sampled beats to layer in with the song I’m mixing with. I have a theory as to what is happening. When you press the sync button and hold it depending on when it switches over It may have to speed up or slow down to match and sync in with the cloned song and that is what is causing the BPM change for a few seconds till it catches up. Therefore it’s probably a matter of timing when you hold down the sync button that determines if it will cause a temporary BPM change. The problem is there’s no way of knowing how to get the timing right since when you hold down the sync button it doesn’t immediately switch over. So unless there’s some way they fix it in a firmware update the work around would have to be to have one deck not being used. But as is I enjoy using all four decks at the same time. So by doing that it limits my creativity.