If you're using a plug in wall type charger, you may be seeing the best it can do for a non-peak type charge. The rx pac may beed some cycling to really come into its own due to the time its been sitting until you bought it. Mine have needed a few cycles to improve and then stabilize as far as performance.

Peak charging delivers the optimum charge the batt can accept and its a diff type charge than just leaving it plugged in overnite. If thats all you have access to, plug it in and leave it much longer and see how much improvement that shows, just check it once in a while to make sure its not getting too hot.

Do youknow what charge rate your wall charger has? If its low (only a few hundred milliamps) this may be just too little charge time.