2012 Custom 1st gear problems

[Ducati0]

When selecting 1st gear, unless it’s really forced into position, it will unselect when lifting clutch. It’s not popping out with a Big Bang, but more of a crunching sound like trying to select without clutch depressed.

Once it’s fully engaged, it stays in 1st & the remaining gears are all ok.

Any thoughts what it could be ?

Thanks

[p2thed]

Worn syncro in the box, it will need the gearbox out and stripped.