A satellite-based digital audio radio (SDAR) receiver is configured to
temporarily store data that may be transmitted to the SDAR receiver at a
time inconvenient to the subscriber. A memory arrangement buffers data
output by a channel decoder. The SDAR receiver can use the buffered data
prior to using any currently transmitted data. The buffered data is
associated with buffered timing information that lags behind the current
timing information associated with the currently transmitted data. The
buffered data is available for use only once before a decryption
subsystem receives the current timing information. If the subscriber uses
the currently transmitted data, the decryption subsystem receives the
current timing information. The decryption subsystem decrypts only data
that is associated with timing information that is no earlier than the
latest timing information received by the decryption subsystem.
Accordingly, the buffered data becomes unavailable once the decryption
subsystem receives the current timing information.