Credit Card process hangs

We are running into a problem with processing credit card orders.  When our shipping department ships the shipment, it's kicks off the process to charge the customer credit card.  90% of the time this comes back successful.  10% of the time it appears to hang and the user has to restart Epicor(9.05.702a).  When they log back in and check the order, the money has been taken successfully and the order has been closed.  Anyone else experienced this and found a fix?  Thanks.