the drives do go bad on these
i have repaired several of these units with bad drives.
i just buy a second unit that has the dreaded "Loading" error and swap the DVD drives
you can find broken ones on ebay
the DVD drives from the DR-MV1 & DR-MV5 combo decks are much better
with minor mods to the bracket and wiring you can use the DR-MV drives
and it is a DR-M10 not a DM-R10
the DR-M100 is an even better unit