Newbie - HT813 Outbound Call Issue


Hi, I’m a newbie and have been using these forums to configure the HT813 to work in the UK with 3CX. So far so good and I can make and receive calls using the FXS port both internal and external.

I can also receive calls via the FXO port from the PTSN, these are both routed to the FXS or other extensions by 3cx.

My problem is when I place an outbound call to the PTSN via the FXO port all that happens in the extension on the FXS port rings. I have searched the forums and 3cx and connect see this being reported. I’m at a loss to which settings should change to prevent the FXO port routing calls to the FXS port. These are outbound calls not inbound.



Did you register same sip account on FXS and FXO ?

As for FXO, check FXO page: ring call thru FXS (or something like this is at end of page)


Hi, thanks for the fast reply.

They are different 3cx accounts, one is an extension and the other is a Trunk. I have double checked and Ring Call Thru FXS is set to No.


Which version of 3cx and did you configure the HT813 via templates or not?


3cx version is 16.0.622. I set-up the Trunk as a Generic PSTN Gateway


Look this is not the 3cx forum and your issue is with how 3cx deals with the HT813 I think - check out the post here -->


You can try and play with loop current disconnect threshold or, disable the loop current all together.set wait for dial to yes, stage 1 with a dial delay of 500 Ms.


Hi, thanks for the replies. I have Unregistered the FXS port from 3cx and it still rings. Checking the syslogs 3cx is passing the correct phone number I dialled to the HT813. For some reason, I think the dial plan or something is not quite correct and therefore the default reaction seems to be the ring the FXS port.

I will play with the settings suggested above.


Yes, it will show the FXS ringing when the FXO is unable ot dial out.

I use the HT in hotel installs with 3CX, with quite a few out there across the US.