The Lochranza Hotel does indeed have a guitar hanging on the wall ready to be used, and the bar has a good atmosphere. The village hall hosts a family ceilidh every Thursday this summer, featuring the Boguillie Band (pronounced Boglie). Less than two miles away, the Catacol Bay Hotel is a fine place to stay and to eat. There used to be music there but it's more of an eating place now.
Incidentally, Mrs. Scarecrow and I got married in Lochranza, had the reception and a brief honeymoon in Catacol, and now live in a nearby village.