I recall reading about complaints of gearbox whine, only in certain gears, on the earlier model V-Strom. Those with knowledge, spoke of it being due to the straight cut gears, that are known for often causing the whine. If you make use the site's search facility, I'm sure that you will receive a few hits in your search. Basically, as long as the engine oil level is OK and the chain is lubed, the advice is to wear ear plugs when out riding.