No, initial time stamp values are picked randomly and independently for each RTP stream. (This is more or less unavoidable if different media types are generated by independent applications, whether these applications RESIDE on the same host or not.) Synchronization (such as lip sync) between different media is performed by receivers through the NTP timestamps in the RTCP sender reports. This timestamp provides a common time reference that associates a media-specific RTP timestamp with the common "wallclock" time shared ACROSS media. The mechanism how end SYSTEMS synchronize different media is not prescribed by RTP, however, a workable approach is to periodically exchange MESSAGES between applications to indicate what delay each application would impose on the stream (including any media decoding delays) if it were not to synchronize and then have all applications choose the maximum of these delays.

No, initial time stamp values are picked randomly and independently for each RTP stream. (This is more or less unavoidable if different media types are generated by independent applications, whether these applications reside on the same host or not.) Synchronization (such as lip sync) between different media is performed by receivers through the NTP timestamps in the RTCP sender reports. This timestamp provides a common time reference that associates a media-specific RTP timestamp with the common "wallclock" time shared across media. The mechanism how end systems synchronize different media is not prescribed by RTP, however, a workable approach is to periodically exchange messages between applications to indicate what delay each application would impose on the stream (including any media decoding delays) if it were not to synchronize and then have all applications choose the maximum of these delays.