You may want to try a non_Sooloos approach to backup and sync.

Search my posts from a year or 2 back for the process I use.

It does not crash or have any funnies.

Essentially copy the full Sooloos library share from the MD600. Take that with you and simply re-sync it to your other unit. Use a data sync program to do that. I find freefilesync excellent for this purpose.

Once you've done the mother-of-all syncs everything thereafter is incremental.

Rgds,
Nick