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Andrew Skelly
Rising star

88XX offhook/onhook issues

Has anybody encountered an issue where your 88XX (specifically 8851) phones have randomly exhibited off-hook/on-hook tendencies?  Over the past year we have had upwards of 250+ phones randomly go off-hook then on-hook in less than a second, sometimes causing active calls to be dropped.  Different hardware and firmware versions but the symptoms are always the same.  TAC hasn't found anything yet, so I'm just trying to gauge if this is an issue others are having.  Thanks.

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Ratheesh Kumar

Hi there


Not with 88XX. Below are the same behavior with 7900 phones


7942 / 7962 phones go off-hook and then on-hook 400 milliseconds later
Bug ID  - CSCto78441
7962 phones are going off hook and then on hook 400 milliseconds later, which prevents the user from answering the call properly. This behavior can be seen in the SDI traces:

11:33:42.540 |StationInit: (0000030) OffHook.|1,100,49,1.584290

and then back on hook roughly 400 milliseconds later:

11:33:42.981 |StationInit: (0000030) OnHook.|1,100,49,1.584297

This can occur on 7942 or 7962, and is more likely to occur when the phone is sitting at a steep angle and especially with a sidecar attached.

1. Invert the wall mount tab to be in wall mount mode.

2. Reduce the angle at which the phone is sitting by two notches. This may not be possible if a sidecar is mounted.

3. Do not use a handset, use only a headset.

4. Open a case with Cisco Customer Service or Cisco Technical support to have the affected handsets replaced.

Hope this Helps

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Has there been any update to this issue? We are having the same issue with a couple of phones on our network, one actually on the network and the second one registered back thru the expressway. 

We had Cisco AS out to one of our sites to observe the issue.  They saw it first hand and recorded the issue to confirm it is happening.  They sent the offending phones in for hardware analysis.  Their conclusion was that there was corrosion on the hook switch.  Whether or not that was the cause of the issue for the dozens of phones we had/have with this problem I cannot say, but the one that they analyzed had corrosion on it.

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Any additional updates on this condition?  We have this issue with Cisco 7841 phones running Firmware load sip78xx.12-5-1SR2-2 on CUCM Version  (Phones were purchased new almost 3 years ago)  This mostly happens with users who are working from their home so it is registering through our MRA server.  Once it starts to happen on one of the phones nothing seems to make it stop going off-hook and back on-hook continuously.  We have recycled the phone power as well as the home router that it is plugged into as well as resetting the phone back to Factory defaults) This is very disruptive for the user - especially UCCX Agents who's Finesse state continuously changes from Ready to Off-hook and then back to Ready.  


I end up shipping the Remote user a different 7841 phone to resolve the issue.  Once I get the replaced phone back and I plug it into our Corporate Network the phone seems to start behaving normally again.  Unless I'm just not giving the phone enough time to fail again.



Why are you using Cisco Hardphones not Cisco Jabber which is much easier to manage in my sense rather CP-7821.

I am seeing such a scenario first time so would not be able to comment much.

Just curious, does the agent able to login to Finesse using that phone?
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regards, Ritesh Desai

For a small percentage of Agents that prefer to use a hardphone we have their hardphone configured as the Associated device in the CUCM RMCM Application user so their Finesse client controls their deskphone.

We use a mix of both Jabber and Deskphones with the large majority of Agents using their Jabber Softphone.


Easier to manage?  Perhaps.  Much more susceptible to audio quality issues?  Absolutely.  Jabber is fighting for laptop/desktop resources (cpu, memory) with everything else running on the machine.  A hard phone isn't.  For an agent taking customer facing calls you want the best audio experience possible and you are most likely to get that from a hard phone (as long as it doesn't keep going off-hook/on-hook and dropping calls).

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No additional updates.  Cisco is sticking with the "corrosion" theory on the handset terminal.  Ironically we are seeing this predominantly at work at home phones as well.  We were able to recreate in the office when we had a defective phone sent back in.  Replacement of the phone has been the only fix.

One way we have been able to see the on-hook/off-hook issue is by looking at the console logs on the phone itself. for "is_onhook".  One of the phones we saw with this had 27 instances of this in 3 minutes.  A value of 0 means the phone is NOT onhook and a value of 1 means the phone IS onhook.  So 13 times in 3 minutes the phone went offhook.  This value only appears when the phone goes off cradle, not speaker or headset.

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YES, I have this exact problem going on right now, but with a 7841 phone. This has no relation to any 79xx model phone or its simple 'angle' problems, as this is a MRA phone. I'm starting my quest to figure it out now. I will remember this post if I figure it out. 

Here is my answer from Cisco TAC about this, as it pertains in my case of these annoying off-hook/on-hook conditions which come into our help desk as tickets for phones 'chirping', as in the noise that comes out of the built on speaker when the off-hook/on-hook condition exists. My temp fix is to replace the phone now. In my organisation we do not have Presence, so the fix regarding IM&P is not for me. I haven't done any of this yet because we are upgrading next week to 11.5 above (SU2) because of an even bigger problem with when you enable 'SIP Path Headers' on the Expressway-C (and we do this to support multiple lines on the MRA phones), it breaks our call recording built in bridge setup. 


Problem Description: 7841 MRA/Expressway phones will periodically go into a cycling state of off hook/on hook by itself.


Action Plan:

  1. Description: A defect with BLF Speed Dials in CUCM that causes TCP connections to close due to illegal value in the "expires" parameter.

    Possible Symptoms: It presents itself in different ways: trunk resets, no audio, one way audio, and the phone rings, but when call is answered it gets dropped.

Details: The system is affected by CSCuu06649. Communication between Unified CM and Expressway-C is unstable and can affect MRA calls and logins.

Workaround:  Disable BLF speed dials by going to CUCM > System > Enterprise Parameters Configuration -> BLF For Call Lists : Disabled

If you cannot apply this workaround you need to upgrade your CallManager  to version 11.5 (SU2) or above.

  1.        Details: MRA is configured on the Expressway but no domain is activated for IM&P. Your MRA users will be in phone mode only.

    Action: Go to Expressway-C >> Configuration >> Domains and add a domain for IM&P






Well, we upgraded CUCM to 11.5(SU8) over the weekend and I still have 'chirping' phones going on in the company, so I dont know what the problem is now. I am just sending the MRA home users another 78xx phone. Luckily we dont have but 2 of them doing it, plus my own but I just unplugged mine and shoved it in the closet and got another one, no more silly off-hook/on-hook problems for me.


My organization is also experiencing the issue.  It is occurring on 8845 and 7841 phones globally.  It occurs on phones in offices and on production floors (unconditioned spaces).  We have sent phones to the software and hardware BU, without resolution.  The problem we see are sporadic on/off hook while the users are using the phones, and when the phone is at rest, untouched.  The incident rate is typically around 1-5 devices a month.

1 of our 8841 phones started experiencing on/off hook cylcing. you can be on the phone and will hangup or off hook without touching it or lifting the handset

was anything figured with this issue?


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