Micro Plus 600 Boat

Micro plus 600 cabin boat with Suzuki dt 85 outboard 2 stroke engine just had a new boat safety certificate I've not used the boat for a while and ive used it a couple of times this year and the engine has played up a couple of times cutting out after a couple of minutes of idling but if you rev it its ok somebody at the marina told me it might be something to do with the timing that might need setting up but I'm not sure please call for more detailsphone