I went to Best Buy yesterday in Frisco, TX located at North Dallas Tollway and El Dorado to exchange a gift. Their was one girl behind the counter who was very helpful. She told me where to go to find my new item. I found it and went back to service desk, there was a line of 5 people waiting with various issues. The Customer Service Girl was dealing with these people and issues as efficiently as possible, but it was taking some time. She called for manager support several times but it took about 15 minutes for a young manger to saunter over to the counter. Meanwhile I could observe several groups of sales persons talking with each other. The store was not busy at the time.
My suggestion would be to cross train your sales force in customer service procedures so that they can recognize a line and get behind the counter and assist customers. And managers need to respond immediately to manager requests. There were several irritated customers wasting their time grumbling with each other as we waited in line.