Increase in declined credit cards? AVS?

Last week (opening week, of course) we saw a significant uptick in Box Office calls that customers were getting their cards declined online. This week we’re already experiencing multiple calls a day and I’m sure there’s an order of magnitude of those who aren’t bothering to call and completely abandoning their purchase. This could be relative to the overall increase in sales as the season starts, but it’s still alarming how many we’ve received.

Has anyone else been experiencing an increase in the last few weeks?

We initially thought it was due to having AVS turned on because if the Primary Address on the account does not match the credit card, it will decline, and for the most part that seemed to be true of the calls coming in. The reason we started doubting this theory was because on one of the calls today, the guest’s two addresses matched -- the only difference was that her zip on her primary account is the 5-digit zip rather than the 9-digit that comes from AVS – is AVS this sensitive?? According the documentation, AVS should be approved based on zip code. (There is also a chance her decline was a coincidence, but I’d rather not write it off at this moment – she was able to purchase tickets by phone).

We’ve decided to turn off AVS and see if we see a change in the number of calls. (We initially turned it on because scammers were using the donation process to test stolen credit card numbers with small donation amounts, so we're a bit hesitant). In the meantime, I’ll be monitoring this closely.

Has anyone else found a solution to this problem?

Any experience / feedback would be greatly appreciated!