New Trey Songz Video

A new video from the Trey Songz saga shows he had a good excuse to take off his mask at one point during the Chiefs game -- but it won't help his case with cops.

As you can see, Trey's face mask was in chin strap mode as he chowed down on a cup of french fries. While masks were required for all fans, the stadium does allow an exemption for eating and drinking.

However, we're told this was about 10-15 minutes before the KCPD officer came over -- backing up 3 visits from stadium security -- demanding Trey pull up his mask.

The other interesting element to this new video is that you can see there are at least a couple other fans watching the fight who didn't have their masks up.

It does make ya…