I have the updated software installed 4.510 and have activated navweather with XM. I then purchase a AS RSL Wireless Sonar Link unit. When first connected with everything else, it does the something as the XM unit. So I tried connecting one accessory at a time to the com link cable. Everything works good until I connect the XM Weather unit. At which point it and the Wireless Sonar keep disconnecting and reconnecting about every couple of minutes, But the BP WeatherSense and GPS don't lose communication. When I disconnect the XM unit and keep it unconnected, then restart the head unit everything appears to work fine, Including the wireless sonar. The XM unit was mounted 6' away from the head unit. I've then removed the XM unit from the boat and tried it as far as the 20' cord could reach to see if it was to close to the head unit and it keeps disconnecting. Even when it is hooked up alone to the unit with only the GPS connected.