VoLTE Mute Call Issue and One Way Audio Issue

4G LTE
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1

Hello Experts,
We are facing many mute calls and one way audio issues. Can you please highlight the possible areas we need to check to resolve the issue?

Network: NOKIA RAN with HUAWEI MME and IMS.
VoLTE Network.

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Check if you are facing frequent Handovers and RRC Reestablishments or LTE Drops.

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Packet Loss could be also the cause.

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There might be many reasons for the VoLTE Call Muting:

  1. Frequent RLF- Optimize RLF timers (T311,N311,T310,N310)
  2. Check RRC Reestablishment rate. - Should be as low as possible.
  3. Optimize A3 Offset/ TimetoTrigger A3.
  4. Optimize B2 thresholds

Generally VoLTE Mute calls happens during mobility and Weak coverage zones, Try to optimize HOs.

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MCR causes

Back haul- check GTP loss and TX pkt loss L2 switches .Router configuration,physical connection etc
Intereference-external and internal
RF coverage
RF quality- SINR RSRQ BLER ETC
Poor hand over MRO too early or late
Hardware issue

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try to modify scheduling strategy for QCI1,delay based is most recommended for QCI1.

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I’m looking at one PCAP from eNB, trying to solve one way audio calls.
Need if someone knows clarification for RTP streams.
Some streams looks very anomaly, with abnormal lost rate and when I check those particular problematic RTP streams there are a bursts in some moments with repeated RTP packet (100-150 RTP packets).
Literally every RTP packet is repeated after a few rows.
So I cannot understand how is possible that RTP packet is repeated at all and how is that handled at all in UE?

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Experts,
What could be the reasons for VoLTE one-way calls or repeated calls in 3G caught from traces w.r.t core or Tx side if there is no issue found on radio side?

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Dear Experts,
Someone have suggestions for One Way Mute Call?

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Thanks Ravinder!!! It would be great if you can throw some light on media gap calls vs mute calls.
What is thresholds for same in seconds & how we can ensure at counter level that media gap call is reported in counter with continuous gaps? I haven’t seen any separate counters for media gap calls.
Thanks in advance !!!

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