Hello Peter,
I would take it back and give them the opportunity to make it right. It might be something very simple...new strings and a check of the setup. I don't think you are being heavy handed to ask for your guitar to be made right. Any competent guitar shop or guitar dealer from whom you have bought a guitar should strive to make it right with you. You are, after all, the customer and the customer is always right.
I am unclear as to whether or not this guitar is a new guitar or it is new to you, i.e., "pre-owned." In either case, it seems to me that you only have a short window of opportunity to have your concerns addressed. After enough time goes by, I'm guessing...30 days or so...the guitar shop could say that you caused the problem...and that's probably fair on their part...they give you (in this example) 30 days to determine if the guitar has any problems which didn't show up at the time of purchase.
I'm sure that if you maintain a cool head, the guitar shop will try to make it right with you. If a particular sales person is uncooperative about the situation, then ask for the manager. Surely, he or she will listen. If not, I certainly wouldn't do any more business there. It is in the guitar shop's best interest to keep you happy.
One way or the other, they should either fix the guitar to your satisfaction or offer to take it back in exchange on another guitar.
I don't know if this helps but I hope so. Keep us posted with how it turns out. I hope you get your guitar problems resolved.
Best wishes and Happy New Year,
BH
[FONT=Verdana]Bobby Howe[/FONT][FONT=Verdana]Alias: guitargeorge50[/FONT][FONT=Verdana]Guitar Tricks Instructor[/FONT]www.bobbyhowe.comBobby Howe's My Space PageBobby Howe's Facebook Page[FONT=Verdana]"Guitarists should be able to pick up the guitar and play music on it for an hour, without a rhythm section or anything." - Joe Pass[/FONT]