Have an XM receiver that interfaces with dual AFS 4500. Done through ethernet hub. For months I have intermittent displays from XM due to receiver cycling from active to idle according to diagnostics on AFS. Some flights OK and others will see cycling and then data light on XM will go out. Then power light will go out after another 5-10 min. Have tried independent pwr to xm. Replaced the ethernet hub and seemed to work ok for a month then started again. Leads me to suspect the ethernet hub. Wondering if small voltage fluctuation could be causing as the hub is designed for 12v powerpacks. XM seems to work fine outside the aircraft. when I bypass the hub ie go direct to one of the 4500's seems to work ok.
Anybody have a similiar experience or any ideas more than welcome