High jitter value observed by remote party
Check if this is a network condition rather than problem with transmission.
Since the transmission of the RTP packet is driven by the sound device clock (see Understanding Audio Media Flow page for the complete explanation), the performance of the transmission is affected by the performance of the sound device. If the sound device doesn’t deliver the captured frame in timely manner, the outgoing RTP transmission will have jitter in it. See Checking the quality of the sound device for more information.
Note that normally a jitter in the transmission shouldn’t cause problems, since the jitter is not very big and the receiving party should be able to accomodate this with a de-jitter buffer.