Hello @David_Haaf,
Thanks for contacting support, I’d be happy to assist here.
Can you please let me know how your are mounting your Drobo in Roon? Are you using IP address, hostname or a USB connection? How is your network set up here? Please list the model/manufacturer of your router, any switches you have and how your Core and NAS are connected to the network.
Generally speaking, when the amount of tracks erode or albums are missing such as in your case, it can be often traced back to network instability or issues with the NAS itself. One such case of the NAS itself having a failing hard drive can be found in this thread (Slow to operate and skipping a lot [Solved]).
With that said, can you please try running a disk check on your Drobo to see if there are any bad sectors? I have found these instructions from Drobo’s support site. The behavior you’re describing here would also be consistent with a damaged cable, if you have another USB or Ethernet cable to facilitate the connection to the Drobo, can you please try to replace it to see if that resolves this issue? Please let me know your findings when possible.
Thanks,
Noris