Once the above critical update is installed, the PNA will lock up for about two minutes if the minus sign (-) is entered as the first character in the active entry area of the PNA. For example, pressing Preset, Power, and the "-" sign will exhibit this behavior. This only occurs via the front panel; an external keyboard works okay. Once this occurs, one must either wait about two minutes before control returns, or you can terminate the PNA application using Task Manager.
Download and install this small patch. The PNA application should be closed prior its execution. Installation takes only a moment. All versions of the PNA from A.02.xx through 3.xx should have this patch installed. This problem is now fixed in the current firmware of A.04.06. If you have firmware version 1.xx installed and you do not want to update to 2.xx or 3.xx, then the Microsoft patch should be uninstalled.