EHS cable won't pick-up call on gxp2160



Hi ! i’m trying to use APD-80 EHS cable alone (no extension cable) with my 2160. Headset works partially. I hear dial tone when Headset key active. But it won’t hang up when pressing the button on the headset. I don’t hear a tone or ring when the phone rings. So obviously it won’t answer the call if i press the button on the headset. Phone version is It never upgraded to the latest I always get «Recovery incomplete» after a long while. UCM version is just upgraded.
Phone config for headset is Headset key mode : i tried both Default and Toggle rebooting phone after each change. Headset type = EHS. Headset ringtone = EHS. Always ring speaker = i tried both settings rebooting the phone each time.
Nothing has made a difference. I also found a procedure to do on a headset provider’s web site for such a condition. Unplug the ehs cable. Unplug power on the headset base for 60 seconds. Plug everything back in. No result. I know for sure everything is OK with the headset and ehs cable since it works perfectly on a 1782 that i have. Any idea what i have been missing ??


You need this as well -


Thanks for your reply on a Sunday !!! Why is that ??
isn’t this cable just an extension to allow us to use the cable path on some phone models ??


Perhaps I spoke too soon as I failed to ask - what model of headset? I use Plantronics and am an authorized reseller and use quite a few with GXP21XX phones, which when I saw the post for the 2160, I just assumed the same CS5XX Dect headset that I normally see and use.

The cable adapter cables provides the needed signaling conversion from the phone to the base for hang-up and answer.

You can also see the requirements in the attached -


WoW !! Thanks very much for this point of clarification. I read about that cable but all i found was that it was just an extension cable. And since that headset worked just fine with my other model 1782 without that cable, i thought it was not absolutely required. I will certainly get one of these to test. By the way, your assumption was right. I use a CS540. Thanks again


I was wondering why I couldn’t get remote answering to work, I normally throw out this lead.

So you’re saying with this lead attached, remote answering and hangup will work?


It´s not the adapter that is shipped with the headset.
It looks almost the same,but it´s other wiring.
I can confirm that remote answering only works with this adapter Larry told.


Bought the adaptor, attached and tested and can confirm it works.


Great. Glad you got it working. Will mark as solved.


Hi IpNeblett, you mark this post as solved but me, who posted it in first place could not yet make my tests since that cable is backorder at my supplier. I hope I will get the same result as Telefonix did. (without prejudice !! :slight_smile: )


My apologies as I mistakenly saw the “I got it to work using the cable post” and assumed it was from you (original poster) without looking.

Hopefully, you should have no different of a result as the need for the cable was confirmed by 2 others and I have quite a few number of folks using the same without issue.

You can continue to post if needed, but hopefully anyone else who has the same issue, may see the post and the solution should have the “same”.

Let us know how it goes when you get the adapter.


Jumping in for a related issue with the EHS.

Anybody else having a 4-seconds delay on pickup with this specific cable combo?

I tried a weird work around… setting the headset button to “toggle headset/speaker”, it works for a while, but then the delay comes back… any one?


@agermain, for best results and least confusion, please open a seperate topic when asking about a different issue.


You’re right, I will, thanks.


Hi. could you please explain to me how you plug it to the phone? with 85638 adaptor,

its RJ11 connector, i cannot figure out , how it may works…

how you fit the APD-80 with this adapter cables…

thank you very much


APD80 Adaptor->85638->Headset Port


For any Plantronics Headset - use the compatibility website see what I use here

It always helps me choose the right components for the Grandstream handsets.



Hi to you all,

Now I took the time to take my wiring measure device to have a closer look what happens if a
PL-85638-01 Cable Adaptor is used.

Exactly as I already suspected in a previous posting (which unfortunately I can not find), only the assignment of the pins is changed here in the adapter. A subsequent opening of the adapter housing also confirmed that no electronic components were installed here.

The RJ10 connector of the APD-80 (towards phone) only needs to be rotated 180 degrees.

So if you have a crimping tool and a RJ10 Western plug, then you can do the whole thing for about 2 cents.

If you use a lot of devices then you can offer your customer a price advantage

With 20 adapters, the price of an additional headset has already been reached.

In addition, it is eliminating another plug connection, which of course can always be an additional source of contact issues (and does not look very professional,too).

Best regards, and have a lot of fun…



Always pays to look inside the box.

Well Done.


Yes and I love it :sunglasses: