[Samba] Pcloud and Rclone: NUL added to beginning of each file

[Alessandro Rinaldi]

Hello,
I'm experiencing a really strange behaviour with Samba that I can't easily
debug.
I have a pCloud account mounted using rCloud (Fuse file system) with the
following command:

rclone mount --allow-other --umask 0007 pcloud:/ /media/alerinaldi/pcloud

The mounted directory is then shared with Samba in read/write.

It all seemed to work like a charm, except for a really strange behaviour:
every time I copy a file from a Windows PC to my share, a NUL (0x00)
character is added to the beginning of it, and the resulting file is then
corrupted (even if easily repairable).

It doesn't happen if I copy a file directly inside the server to the
mounted directory, neither it happens if I copy a file to a share referred
to a local filesystem.

I really can't get what is wrong, if it is a matter of Rclone or of Samba
itself.
Do some of you have suggestions on where to look at for debugging?

Thanks