[wesk05]

Its a techonoly problem not a BUG from the Shield

It was working fine before! What changed is how the Shield enforces and polls HDCP status. It used to be that HDCP was enforced only when the content required DRM. That changed with update 3.1 and now HDCP is enforced as soon as you see the Android logo during boot. It doesn't look like nVIDIA will change this and so, this refresh rate switching issue will remain for ever.

Someone may need to test this possible solution...

HDCP 2.2 Shield > HDCP 2.2 AVR > Blackbird 4K Pro HDCP Converter, 2.2 to 1.4 > HDMI 1.4 Display

Technically, it will work. I haven't checked it with update 5.0.