1. A method for tracking content rendered on a content-rendering device that is communicably coupled to a content server, said method comprising: sampling by said content-rendering device, an audio component of said content at a sampling rate; generating and communicating to said content-server, an audio fingerprint based on said sampled audio component; and modifying said sampling rate based on a detected scene change in said content, wherein said scene change is detected based on said communicated audio fingerprint.