A system for receiving and decrypting media content encrypted according to the HDCP protocol is described herein. A receiving device coupled to a plurality of content channels includes an authentication engine to authenticate each content channel and to generate an initial session key associated with each authenticated content channel. The content channels can be, for example, an HDMI channel or an MHL3 channel. A session key indicator indicating a session key used to encrypt media content is received, and an updated session key is generated. The receiving device also includes a stream cipher engine configured to decrypt received encrypted media content using the updated session key. Decrypted media content can then be displayed, for instance on a display of the receiving device.