Let me transcribe a problem that has been detected by a partner, using a FX9500:
Using the object Symbol.RFID3.RFIDReader, when recording a tag with the method Actions.TagAccess.WriteEvent (AccessParams, null, Ants), it works correctly for a while. But there comes a time when doesn't launch the event Symbol.RFID3.Events.STATUS_EVENT_TYPE.ACCESS_STOP_EVENT. From here, any attempt to read or write returns an exception. In general, any access to the API. The exceptions return texts as "ReadWait", "ReaderCapabilites", "GetConfig", etc.
You have to disconnect and reconnect to back to work, without re-creating the object.
Could you advise?