Seems to me the Minstrel job is based on how many PCs are in the area when you use it? Could be wrong.
*edit* Yup
Minstrel Job Entry wrote:
How does it work?
NB: You need to be able to use Perform for this job.
You start your performance by singing within range of a Minstrel Instructor. You will get a message that the show has started.
You end the performance by singing again after at least 5 minutes.
You get to roll for XP for people that have been within hearing range during that time.
http://www.amiaworld.net/about/ds_j_jobs.php?job_id=71