69xx Phones act like they execute RTPMRX but do not play audio 9.2.1

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    This document was generated from CDN thread

    Created by: IAN PITTS on 22-08-2011 08:47:58 PM
    We have confirmed that with the upgrade to CUCM 8.6 the 6900 series phones running 9.2.1 do not allow 
    This behavior causes catastrophic failures fro applications using the RTPMRX features and does not exist on the other devices we have tested against on CUCM 8.6

    Behavior is like this. 
    <li>If you send the devices a RTPMRX the devices never receive the audio but reply with success.A sniffer capture shows that the phones accept the command ad even reply with success. However the phone never opens a receive port for the audio and then sends an ICMP Port Unavailable for every RTP packet being sent. </li>
    <li>The phone even acts like it is playing the audio by turning on the speaker and mute buttons but no audio is played due to the phone not accepting the packets. </li>
    Has anyone else seen this issue?
    I did a quick bug scrub and noticed many bugs that relate to IP Phone Execute and multicast audio reception.