If you are willing to do a little research on modems, this link will most likely have the answer.

Usually, you want to go into Device Manager, select the modem and click on the Properties button, select the Driver Tab up top. Then click on the Driver Detail button, in there you should see what version driver you are using.

You may be using 8.20 or 6.04 versions, if you have the later you may try to update.