This excerpt taken from the SIRI 10-Q filed Nov 12, 2008.
Interference from other users could damage XMs business.
XMs service may be subject to interference caused by other users of radio frequencies, such as RF lighting and ultra-wideband (UWB) technology and Wireless Communications Service (WCS) users. The FCC is seeking comment on proposals by certain WCS licensees for modification of rules regarding their operations in spectrum adjacent to satellite radio, including rule changes to facilitate mobile broadband services in the WCS. We cannot predict the outcome of the FCC proceeding, or the impact on satellite radio reception.