Arduino Yun with PoE does not work when powered via PoE
PoE Adapter

Silvertel AG9600 1R requires a 100µF 16V Electrolytic Capacitor between it's PIN 7 and PIN 8

According to the PoE Yún Thread the capacitor polarity should be as follows:


  PIN 7 --> Capacitor_Negative. PIN 8 --> Capacitor_Positive


solved my problem. I think the default 470uF capacitor might not be able to charge-discharge appropriately with data signals in the PoE.