[YMCS/YDMP Free Trial Program]Yealink would like to offer Free Trial Program of Yealink device management service for our current eligible customers. You can see the details below.
https://www.yealink.com/ydmp-freetrial-2020


Post Reply 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
T28P Handset Noise Problems
Author Message
fdtcloud Offline
Junior Member
**

Posts: 18
Joined: Oct 2013
Reputation: 0
Post: #1
Exclamation T28P Handset Noise Problems
We have around 100 yealink T28P phones deployed and counting, however recently we have been noticing trouble with a few T28P handsets. The handset begins to make a loud hum and buzzing noise and will not stop until the handset (just the handset not the entire phone) is unplugged for about 8 hours, then it sounds good again. The temporary solution has been to replace the troubled handsets and they work just fine. Is this a known issue?
02-20-2014 07:18 AM
Find all posts by this user    like0    dislike0 Quote this message in a reply
Yealink Support Offline
Administrator
*******

Posts: 2,683
Joined: Dec 2012
Reputation: 25
Post: #2
RE: T28P Handset Noise Problems
Hi fdtcloud,

1. Can you tell me the version of T28P?
2. Do you test the handsets to the headset port?
3. Do you mean that when you repace a new handset and phone can work well?

Please contact with your seller for RMA and testings.
(This post was last modified: 02-20-2014 05:34 PM by Yealink Support.)
02-20-2014 04:41 PM
Find all posts by this user    like0    dislike0 Quote this message in a reply
fdtcloud Offline
Junior Member
**

Posts: 18
Joined: Oct 2013
Reputation: 0
Post: #3
RE: T28P Handset Noise Problems
1. Are you looking for a revision number?
2. Yes tested to the headset port the handset still sounds poor
3. Yes I replace the handset and the phone works well and after about 8 hours I can use the "failed" handset again and it will work well for several weeks before having the issue again.
02-21-2014 12:08 AM
Find all posts by this user    like0    dislike0 Quote this message in a reply
Yealink Support Offline
Administrator
*******

Posts: 2,683
Joined: Dec 2012
Reputation: 25
Post: #4
RE: T28P Handset Noise Problems
Hi fdtcloud,

The reason is that your handsets along with helix lines are broken. Please ask your seller for RMA.(Please replace with new handsets along with new helix lines. )
02-24-2014 02:21 PM
Find all posts by this user    like0    dislike0 Quote this message in a reply
braymond Offline
Junior Member
**

Posts: 29
Joined: Nov 2013
Reputation: 0
Post: #5
RE: T28P Handset Noise Problems
I had the same problem with 3 T2xP phones so far. I am an early adopter of Yealink product and I start wondering if I should move to another phone provider ...

It is easy saying to replace them but when I have to drive 30 km to replace a handset, the profitability goes to the grave.

Not to mention it gives my customers bad perception about the quality of products I provide.

Another feedback I got is if you stretch the helix cord too much, you loose or patially loose audio.

Yealink, you should consider improving the quality of your handsets.

Thanks
Benoit
02-27-2014 10:58 AM
Find all posts by this user    like0    dislike0 Quote this message in a reply
Yealink Support Offline
Administrator
*******

Posts: 2,683
Joined: Dec 2012
Reputation: 25
Post: #6
RE: T28P Handset Noise Problems
Hi Benoit ,

Sorry for the inconvenience. Can you supply SN numbers for me? I need to check with our factory about this product problem.
03-04-2014 03:14 PM
Find all posts by this user    like0    dislike0 Quote this message in a reply
braymond Offline
Junior Member
**

Posts: 29
Joined: Nov 2013
Reputation: 0
Post: #7
RE: T28P Handset Noise Problems
4101313044400001
4101313044400116
4100313044400168

Thanks,
Benoit
03-04-2014 09:49 PM
Find all posts by this user    like0    dislike0 Quote this message in a reply
Yealink Support Offline
Administrator
*******

Posts: 2,683
Joined: Dec 2012
Reputation: 25
Post: #8
RE: T28P Handset Noise Problems
Hi Benoit,

Thank you. If any update, i will contact with you asap.
03-05-2014 03:48 PM
Find all posts by this user    like0    dislike0 Quote this message in a reply
fdtcloud Offline
Junior Member
**

Posts: 18
Joined: Oct 2013
Reputation: 0
Post: #9
RE: T28P Handset Noise Problems
Please update the forum or email me too with an update. I have had a few more do the same thing.
03-07-2014 06:16 AM
Find all posts by this user    like0    dislike0 Quote this message in a reply
temp0001 Offline
Junior Member
**

Posts: 16
Joined: Jan 2014
Reputation: 0
Post: #10
RE: T28P Handset Noise Problems
I came across this issue with one handset last week.
I found that when the curly cord is closer to other electrical wires, the hum/buzzing gets worse. I swapped the curly cord with a known good one, and the problem persisted, indicating the fault lies in the microphone.

As others have done, unplugging the handset for a period of time resolves the problem.

It seems that the electret condenser microphone in the Yealink handset can develop an over sensitivity to hum fields if left powered on for extended periods. The microphone is always powered - I discovered this by putting the headset up to my ear whilst holding down the hook switch with my other hand, I can still hear sidetone.

Maybe if an electrical bias develops on the microphone, causing an imbalance on the two microphone wires, makes it is more susceptible to picking up hum and interference. My theory is that disconnecting the handset allows the charge to dissipate in the dielectric of the condenser microphone, allowing it work normally again.

Maybe a potential fix (that the Yealink engineers can apply to new firmware) is to turn off the power supply to the microphone when the handset is on hook?
03-09-2014 12:01 PM
Find all posts by this user    like2    dislike0 Quote this message in a reply
Post Reply 


Possibly Related Threads...
Thread: Author Replies: Views: Last Post
  T28P - OpenVPN TLS error: Unsupported protocol 1sae 0 918 07-18-2023 06:50 AM
Last Post: 1sae
  Weird noise when answering via speakerphone nestman 6 18,662 06-16-2021 03:05 AM
Last Post: nestman
  T28P foward call doesn´t work with 2.73.0.50 Tato 4 11,556 09-14-2020 03:49 PM
Last Post: complex1
Lightbulb Yealink T28P Firmware Upgrade Fails Michelth 11 54,820 06-27-2020 10:13 AM
Last Post: complex1
  T28P LDAP Problem oguzhan 1 7,718 06-10-2020 01:14 PM
Last Post: beldimon
  T28P Ringtones V2.70 Starlifter 22 112,593 11-29-2016 01:47 PM
Last Post: Psilverwood
  SIP-T28P Can't Answer Multiple Incoming Calls Trutelecom 1 8,216 08-31-2016 05:10 AM
Last Post: Trutelecom
  T19 makes humming noise imon32red 1 6,796 08-24-2016 06:49 AM
Last Post: mbello
  No sound on SIP-T23P handset AjN3806 1 6,866 07-18-2016 01:12 PM
Last Post: AjN3806
  T28P 2.61.0.160.rom firmware thankappas 1 7,492 04-27-2016 05:33 PM
Last Post: Karl_Yealink

Forum Jump:


User(s) browsing this thread: 1 Guest(s)

Contact Us   Yealink   Return to Top   Return to Content   Lite (Archive) Mode   RSS Syndication