My concern would be that only one is actually HDCP compliant, and that only that only that input could make the "handshake". The original question said the label was HDC, not HDP. IF it is HDP, not HDC, then it may not be HDCP at all.
Just guessing.

Panny 3000 PJ, 118" Carada, Denon 3300, PS3, Axiom QS8, PSB 5T, B&W sub, levitating speaker wire