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8851 and 8861 (SIP) freeze occasionally




I would like to know if anyone have been experiencing some freezing issues with 88XX phones? 


We first received the phones with the firwamre sip88xx.10-2-1-16 but since the phone was looping through reboots when connected to 2x or 3x 8800 modules, we upgraded to sip88xx.10-2-2-16. Since then, the phones freezes completely from time to time and needs to be disconnected. 

When frozen (which often happens when the calls are transferred to another extensions), there is nothing we can do at all on the phones.


There is no newer firmware  so I'm pretty much stuck here.

I'll have to try our other BNIB 8851 but at least one 8861 and one 8851 have the exact same behavior.



72 Replies 72

I am still having phones freezing, due to firmware; I believe this is due to a memory leak in the firmware. This is not a great fix, but I do have a workaround

What I have done is I have a text file with all the phones that are having the issue of freezing in BAT - and have them scheduled to reboot every week early Monday morning. I have since not received any calls - as the phones will never reach the point where the memory leak causes the phone to stop functioning.

I hope this helps in the interim of this issue.

Richard thanks for the reply. the workaround you gave is feasible only if we exactly know which phones are freezing, in our case this issue is randomly happening across different sites, the customer environment is supposed to be handling more than 2-3k of 8851 phones, we cant have then reboot every weekend.


We are starting to see this issue here.

Screen is visible, and buttons are non-functional. No matter what you press, nothing works.

Only cable un/re-plug works.


8865 - sip8845_65.11-7-1-17 - BEKEM

8865 - sip8845_65.11-7-1-17 - BEKEM

8865 - sip8845_65.11-7-1-17 - NO BEKEM


We adopted the 11-7-1-17 several weeks ago...


i too am facing this issue. my 8841's are running sip88xx.12-0-1es-1 and still freezing.  The time stays current, i can reach the phones web page, however, CUCM shows the device unregistered.

Upgrading the firmware didn't resolve the freezing /phone not responding with the 8851s.  It might kick the can down the curve for a few months.


TAC keeps saying the newer firmware will solve the problem.  We have over 500 8851, but deployed 25 among our IT department to test, started on firmware sip88xx.11-7-1ES-5, when a few phones started freezing, TAC said to upgraded to sip88xx.11-7-1ES-12, everything was stable for two months until a few phones experience a memory leak.  TAC recommended upgrading to sip88xx.12-0-1ES-11, and a few froze, so back to the drawing board.  


The deployment of the reminding 8851 is on hold.  We also deployed over 900 7841, no issues with those, except for not able to install side cards. 





We're also seeing this on occasion with our 8865's. Some have expansion modules, some do not. As others have stated, only unplugging and reconnecting the cable fixes the freeze/lock up.

Devices are currently on sip8845_65.11-7-1-17.


Has anyone had any luck with this?



Are people still experiencing issues with phones freezing? I just had a deluge of phones reporting that UI freezes multiple times. Running 8841 model phones...


Try installing the Cisco recommended power adapter. I found out the phones where pulling a class 4 power consumption on my PPOE. Once I added a PS all the freezing went away. I found this issue to be true on the 8861, 8831, and any 8841 and 8851 with a sidecar. 

We're experiencing the same issue. Curious, what type of network switches are you using? We have meraki switches deployed on our end. 

we are also now experiencing this issue with a small amount of our   8845s. Any fix yet?


We are facing this issue with 700 8845 Phones, is there a fix?

I too have the same problem, firmware sip88xx.11-5-1-18


Upgrading the device to the latest firmware code resolved the issue. Currently, I'm using 11.2.1 MPP firmware code for 8800s.
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