Issue Exporting by Exploding Tracks

Hi,

I seem to be having an issue. Every time I export my project ready for mixing, there is always a track that has no audio on it, usually the first one after the program 001. Why is that? Means I have to go back to the machine, bounce the stem as audio on it's own, am I doing something wrong?

Thanks!

It’s on an MPC X with 2.9.1 firmware

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