welcome to the forum,
maybe you upgraded rclone and then the issue started?
need to figure out if this is a rclone issue or not, do some basic testing
- do
chkdsk
on the source and dest - copy the files without using rclone
- copy the files using rclone, without using rclone smb remote. use native tools to access the share
check out my howto guide about smb
does nothing when used on smb remotes