I've got the same deck with about a 140hrs on it. On mine there has been a little evidence of the belt occasionally rubbing on the guard, but nothing that would suggest that it is a constant thing. I haven't not had reason to look into it but I would imagine it might have something to do with the belt tensioning spring. Not to sound snotty but have you checked your manual for the ability to adjust tension? I know I should know this myself being and owner and having read the manual, just can't remember for the life of me if there is useful information in the manual.
John Thomas taught me how to reply to specific person. Thank you again for your reply and I will be contacting dealer soon.