On the media issue, the pnpqueue is only relevant for pnp discovery of devices, not media. Each time the system detects a device, an entry is added to the queue. If the signature of that device is unknown, then it will go through the process of prompting you to add the new device to your system. If it is known, then it simply marks the device as online.
If you still have that NAS device in your devices tree, then the pnpqueue process will only mark it as online. So first check the device is there, and whether the online tick box is ticked. If it isn't ticked, and ticking it doesn't remain after, say, 5 seconds, then you may have the CIFS/SMBFS issue. You can change the protocol in the share device's device data, it should be set to cifs by default. Change that to smbfs and save, then tick the tick box again. This should then stay ticked.
Once you have confirmed it stays ticked, if you still can't access your media, then I can only assume that it is the automounting process getting stuck, as described above. Reboot, then go to a terminal shell, then cd into a directory on that share:
then ls -al to confirm you can see the contents. Now just leave that terminal shell open and that will force it to stay mounted. Now continue to use that MD/hybrid as normal, if it is that problem then this should fix it temporarily. If so, then you can set up a script to cd into that folder on reboot as a workaround.