BT's Digital Voice adapter kills broadband speed.

[jdmtom]

So we received our digital voice adapter last week and finally got round to installing it last night. 
After being out, got home and parents mentioned the internet had been slower, thought nothing of it as I had left my PC on, presumed it was updates. 

However, It is currently 6.30 am and there is only 3 devices actively using the network, Both my personal and work phone and the PC that I am using to type this. 

Did a speedtest - 2.55Mbps down and 1.48Mbps up with a ping of 771. 
Checked all devices, non are downloading. 
So figured I would try disconnecting the voice adapter. 
Low and behold the speed test after doing this gave the following - 
34.05Mbps down and 5.10Mbps up with a ping of 20ms

This is normal speeds for us. 

How are we expected to use the internet when this adapter absolutely destroys our speeds to the point where internet will be mostly unuseable.  

All three of us work from home and will not be able to do so on 2Mbps down...

[Keith_Beddoe]

@jdmtom 

Are you referring to this device, as it does not physically connect to the Internet, as it connects to the Smart Hub 2 using DECT?

https://www.bt.com/help/user-guides/phones/digital-voice/digital-voice-adapter

Can you make sure there is no other connection to that adapter, other than the phone that is plugged into it?

[licquorice]

How are you 'connecting' the voice adapter? It is just plugged into a mains socket and just acts as a analogue phone socket that connects to the hub via DECT as @Keith_Beddoe says.

[jdmtom]

Yes that is the adapter I am referring to.

Can also confirm that it is connected correctly. Set up as per the instructions provided with the adapter. The plug itself is plugged directly into a power socket. Then the phone connected to the port on the top of the adapter.

This adapter is definitely the cause of the speed restriction. Performed a speed test with it plugged in, getting the low speeds, as soon as I unplugged it. The speeds returned to normal.

As the analogue switch off isn't until 2024/5 I'm just going to leave it unplugged.

Hopefully in that time open reach actually pull their finger out and roll out full fibre to my area

[iniltous]

From your point of view the analogue switch off has already occurred ( more accurately the PSTN switch off ) so the end of 2025 is irrelevant to your situation, presumably your telephony is now DV / IP ( rather than PSTN ) that’s why you were  given a Digital Voice adapter in the first place ,

If you have unplugged it , unless you have another phone connected to directly to the router phone port , then you will  have no telephony service, If this adapter has been sent in advance of your migration to DV , your PSTN service will soon stop , then obviously at some point soon ( not 2025 ) you will need to do something to keep your telephone service working.

Although the evidence is compelling, the Digital Voice adapter is only really a DECT device and shouldn’t have any influence on the broadband side of the router ,  it seems difficult to see how it can be incorrectly installed, so presumably either it , or the router is faulty .

If you connect your regular phone into the SH2 phone port ,( with the DAV disconnected ) does this also affect broadband speed ?, and although apparently affecting broadband speed , did the DVA work and you could make and receive phone calls with it ?

Finally , is your reduced speed with the DVA connected on wireless and wired devices, or is it just WiFi ,(wireless ) devices ,  you could try relocating the DVA to see if it lessens its impact if it’s just WiFi .

[jdmtom]

I'll test the connecting directly to the home hub later today.

With regards to the speed tests, they were performed both on wired and wireless.

With the phone plugged into the adapter, phone was making and receiving calls as expected