'Glee' Star Becca Tobin's Boyfriend, Matt Bendik, Found Dead in Hotel Room

1:56 P.M. PDT -- The coroner's office tells us ... an autopsy did NOT reveal the cause of death.

'Glee' star Becca Tobin's boyfriend Matt Bendik was found dead Thursday in a Philadelphia hotel ... TMZ has learned … and the circumstances surrounding his death are mysterious.

Sources close to the couple tell us Bendik -- a 35-year-old nightclub owner -- was in Philly on a business trip. We're told Tobin was not in Philly when he died.

A hotel maid found Bendik's body Thursday at around 1 PM. Law enforcement sources say the housekeeper found the body on the bed, face down.

Police are calling it a "sudden death" and they do not believe foul play was involved. They also say there's no evidence of suicide. And no weapons were found.

We're told no drugs or drug paraphernalia were found in the room. We know the detective's incident report makes no mention of medications in the room. And the report makes no mention of alcohol.

Bendik was last seen by a manager at a club in Philly, just before midnight Wednesday.

Bendik ran several major clubs around the country, but especially in Los Angeles … where he was the Director of Operations at DBA Nightclub. He also was a co-owner of AV Nightclub.

We're told Bendik was not known as a partier, and friends are shocked and devastated by his sudden death.

Calls to Tobin's reps have not been returned.

One eerie twist -- Sunday will mark one year since the death of Cory Monteith … who died in a Vancouver hotel room from a drug overdose.

DBA posted a tribute to Matt outside of the club.

Shortly before Matt went out Wednesday night, he posted a pic of Becca -- calling her out as his #WCW (woman crush Wednesday).