Webdav reports incorrect disk space

Hi, we are running NextCloud 13.01. The data folder is shared from a NAS over CIFS. We have noticed with this (and previous) versions of NextCloud that Webdav clients report incorrect disk space available. Different clients seem to report different capacities. WebDrive may report a disk as full whereas Mountain Duck will say there is 20 EB available! The web interface is fine. We have had this issue for some time and I am starting to think it may be related to CIFS - is this possible? Would NFS be more reliable? I have seen a few issues like this mentioned before but no clear explanation (that I know of). I should say we have seem this across multiple servers and multiple versions. We usually mount the shares under /mnt/data and map then in the config file. Any advice / guidance appreciated.

Thanks in anticipation…

I don’t know on which external storages Nextcloud can detect the available storage. If there are numbers, they should be coherent between the web interface and other webdav clients. Does mountain duck only give false results on external storage? Not that mountain duck uses 20 EB by default when it can determine the remaining storage. Perhaps open an issue on github.com/nextcloud/server/issues