HSBC Bank Nevada, N.A., Best Buy Inc. Misleading deferred finance charge billing Ripoff Carol Stream Illinois

I have been Best Buy coustomer for many, many years spending thousands upon thousands of dollars at its stores.
I have a Best Buy credit card issued by HSBC Bank Nevada, N.A.
I have always used the deferred finance option on purchases, and always have paid my bill on time to avoid deferred finance charges.
I received my Best Buy credit card statement and it clearly stated prominently in the first box summarizing my account that the new balance was $773.28 and payment due on 6/15/07. I paid the full balance online on 6/15/07 as requested.
I received a bill the following month imposing deferred finance charges of $338.93 on 6/21/07, 5 days after payment in full was made. At the time the deferred finance charges were imposed, there was a $0.00 balance on the account.
I called HSBC customer service, and they pointed out that in fine print at the end of the statement, the full balance had to be paid by 6/10/07 to avoid deferred finance charges.
I explained that their billing is extraordinarily misleading ... at the top of the payment it clearly states that payment was due by 6/15/07, and the balance was $773.28, which I paid in full in compliance with the stated due date and the full balance due. I was in disbelief that they could impose deferred finance charges on 6/21/07 which was 11 days after the promotional period had expired, and 5 days after payment in full was received. How could they impose deferred finance charges on a zero balance?
My pleas to the HSBC supervisor resulted in an offer to waive 1/2 of the deferred finance charges. I refused the offer and insisted on a full credit of the deferred finance charges because the billing is extraordinarily misleading. HSBC refused to make the adjustment, and I asked them to immediately close my account ... I stated and vowed that notwithstanding my many years of being a loyal customer of Best Buy, I would never, ever step foot in Best Buy again.
I then called Best Buy, who was totally nonchalant about the event. Best Buy claimed it could do nothing about the credit card billing becasue the card is issued by HSBC ... Best Buy claims to have no control or access to the credit card billing. Interesting ... Best Buy doesn't appear to have any problem posting charges to the credit card for purchases at its stores, and uses HSBC as its credit card issuer under the Best Buy name, but it can't adjust any of the charges?
Well, of course, I stated to the Best Buy representative that I will never set foot in its stores again, and I would dispute the deferred finance charges and investigate the possibilty of a class action lawsuit against Best Buy and/or HSBC.

Guess I'll look for the nearest Circuit City store from now on.

Raul
Miami, Florida
U.S.A.