My Multiplus II system has been running for over four years now without issue. All of a sudden the GX device has stopped transmitting data. The Tx & Rx LEDs are both off. If I reboot by powering down and back on again it works for about 30 mins. During this time both the Tx & Rx LEDS flash away. Communication is by LAN cable plugged in. Worked OK for years and now it doesn’t. Any ideas or is the Cerbo broken?