【Customization】Expansion Module Is Sluggish When Many BLF DSS Keys Configured
Last modified date: 2021/01/19 Views: 3561

Sometimes, if there are too many BLF DSS Keys configured or an environment problem, the BLF status can't be updated in time due to mass notify message.


Phone may receive too much notify messages at the same time and can't deal with them in time.


1. Reduce the number of BLF DSS Keys. Generally, we don't recommend configured more than 100 BLF DSS Keys in a phone.

2. Change parametersSIP Session Timer T1(0.5~10s) and “ SIP Session Timer T2 (2~40s) under Account->Advanced page , increase the value of T1 will make phone send less subscribe message when it doesn’t receive a notify message.

 Note: In V80 version, the path of SIP Session Timer T1(0.5~10s) and SIP Session Timer T2 (2~40s) is Web interface->Settings->SIP.

Set T1 to 4s

Set T2 to 6s

Disable subscribe for MWI


3. Check the network environment and make sure that same NOTIFY message won't be resent multiple times by your network device.


T1 is an estimate of the Round Trip Time (RTT) of transactions between a SIP client and SIP server.

T2 represents the maximum retransmit interval for non-INVITE requests and INVITE responses

More Information

If there are any other questions, please feel free to contact with ticket.yealink.com

Product Type
LCD Expansion Module EXP20 , LCD Expansion Module EXP40 , Color-screen Expansion Module EXP50 , IP Phone Expansion Module EXP38 , LCD Expansion Module EXP39
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