2011 XT 400 – Grinding Noise w/Braking

Purchased a 2011 Outlander XT last fall for my wife. Only had 172 miles on it. Rode it a little last fall and some over the winter with no issues. This weekend the wife stopped me while riding and said there was a grind noise when stopping and was worse going down a hill. Noise is duplicated even on flat road and braking. Sounds like a loose or worn u-joint of drive chain type noise in center of atv. Pulled cover and checked what I could on clutches. Rear shaft seems ok. Ran on stand and does not do it which is puzzling. Wondering if anyone else has run into something similar?? New to Can Am’s so not sure of all the qwirks yet…