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High Concealment Ratio; Low MOS reported by phones using Transcoder

One of our customers is seeing an issue where the phones are reporting a low MOS score when
the call needs a Transcoder for the call.
The bad MOS corresponds to a high CCR (Cumulative Concealment Ratio),  which is also aproblem
if silence suppression (VAD) is enabled.  (The phones think the silence is packet loss.)

Could the transcoder problem be a similar type of thing?   The time it takes to transcode is being
considered as loss?

If so, are there any setting on the phone or transcoder device that can be tweaked??

Below is one example from our logs.
Customer will gladly provide any information needed.


Here is one example:

  Transcoder addr:
  CM:           -> StartMediaTransmission[0x8a] cid: 47526316 -> DestIP/RTPPort:; ConnectTime: 0x4eef7eded2889; cid: 47526316 -> CallInfoDynamic[0x14a] CallInfo: +40314036707->60377248440[60377248440];
                                                                                                       redirect: 0; ciType: 1; cid: 47526316

          <<<<<<<<<<<<  Call takes place here >>>>>>>>>>>>>>>>>>>>>>>>>>>> -> CloseReceiveChannel[0x106] Closing channel for cid: 47526316; pid: 33557208 -> StopMediaTransmission[0x8b] DisconnectTime: 0x4eef91ef4e43e cid: 47526316; pid: 33557208 -> ConnectionStatisticsReq[0x107] Requesting stats for cid: 47526316; dirNum: 60377248440 -> ClearPromptStatus[0x113] Clearing prompt cid: 47526316 -> CallStateMsg[0x111] State:'On Hook'; li:1; cid: 47526316 <- ConnectionStatisticsRes[0x23] snt:255882; rcv:216100; lost:4; jtr:2; lat:0; dirNum: 60377248440 <-  VQ: 'MLQK=3.7001;MLQKav=2.8505;MLQKmn=2.0000;MLQKmx=3.7001;ICR=0.0000;CCR=0.1554;ICRmx=1.0000;CS=1352;SCS=1219;MLQKvr=0.95'

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