Bang & Olufsen Beocom 2 and 6000 not working

See the answer here from SDM123

Beocom 6000 No incoming calls after switch | Virgin Media Community - 5175763

The Beocom phones not working has cropped up on here many times before and (apart from the above) there has never been a reliable fix reported that has held up over time.

Oh dear i never realised and the Virgin operatives I've had dealings with just shrug their shoulders. With no prior warning the result is we are left with no working cordless phones. This has been a shabby service from Virgin.

My concern with the B&O phones is their age, buy now the rechargeable batteries must have needed replacing several times, I did not see the type used to see if they remain available.

The Beocom 2 (quite a piece of art) and the Beocom 6000 are both described at DECT phones.

Could the B&O DECT handsets be re-paired to say a current BT DECT cordless base unit ? 

https://beoworld.org/beocom-2/

https://beocentral.com/beocom6000

Don't know if this will help or hinder, but this BT thread has some information that may help?

Solved: Digital Voice FAQs - BT Community

It's all rather complicated to someone not digi (or indeed analogue) comms savvy. But thanks to all for trying to help. I think I'll get in touch with the vintage telephony guys who sorted SDM123 Beocom issues out... I'm sure there must be more frustrated people like me out there who want to keep their nicely designed Beocoms going. So surely there is a market for some electronics guys to corner...

There is no market to corner.

We have been with VM since 2017 and I suspect this is barely 10th time similar issues with B&O phones have come on this forum.  It is a memorable topic because is it so rare.

Thanks @goslow, your replies on this subject have been very informative. I had presumed that VM would not be able to fix the core issue, but I have yet to receive a definitive answer, yeah or nay, from the horses mouth as it were.

Will do, they are away until next week.

As suggested by #goslow I contacted the vintage telephony guy (Chris) as used by SDM123. An interesting conversation - the upshot was that the ‘work round’ for SDM123 was simply to install a resistor between the router and the Beoline base station. A more elegant solution was not possible as the circuitry in the Beoline 2 handset was rather opaque and no circuit diagrams have been publicly published by B&O. SDM123’s issue  was diagnosed as being due to an inappropriate current level being supplied from the router which triggers the pick-up circuitry but not the ring functionality. The work round was to stick a resistor in a box that is connected in series betwixt router and base station. Chris did not regard this as a solution as it leaves the inappropriate circuitry in the phone/base station intact. When they return to their shop next week I will be able to send the Beoline base station, the Beocom 2 and the two Beocom 6000’s to see if he can do the same trick he did for SDM123. Although he couldn’t guarantee success. He also said that the B&O phones were the only make he’d come across that have this issue.

Just a little update. I spoke to the our excellent B&O engineer that has installed other B&O non phone kit over the years and he told me that in the last couple of years he's had quite a few queries on the VM/Beocom issue. He has spoken to the B&O mother ship and they aren't interested. He hasn't found a reliable solution despite trying with a number of customers - sometimes his efforts  which are basically a reinstall work sometimes not. Doing a little more AI aided research the following has been suggested using an ATA ( a Grandstream HT801). I think #Client62 uses a similar device but not with Beocoms? Dr AI suggests that with my current setup it should work with no tweaking but I am a naturally sceptical cove. 

                      FIRST FLOOR (Office)
        ┌─────────────────────────────────────────┐
        │          Virgin Media Hub               │
        │          TEL1 Port (Analogue Out)       │
        └───────────────┬─────────────────────────┘
                        │ RJ11 Cable
                        ▼
                 ┌────────────────────┐
                 │   HT801 ATA        │
                 │  (Line Stabiliser) │
                 │  FXS / PHONE Port  │
                 └──────────┬─────────┘
                            │ RJ11 Cable
                            ▼
             Office Virgin Wall Socket (RJ45 Type)
                            │
                            ▼
                 Internal Cat5e Cable Run
        (Already installed – carries phone line perfectly)
                            │
                            ▼
           Living Room Virgin Wall Socket (RJ45 Type)
                            │
                            ▼
                 BT → RJ11 Adapter (Your Existing/New)
                            │
                            ▼
             ┌─────────────────────────────────┐
             │   B&O Base Station (Beocom)     │
             │   BT Plug → Adapter → Wall      │
             └─────────────────────────────────┘

The advice also suggested that if such tweaks were needed they would be along the lines of configuring the ATA as indicated below.

'Optional' ATA configuration setting tweaks for the ATA FXS Port:

Impedance: 370+620||310nF

Caller ID Scheme: ETSI-FSK

Ring Frequency: 25 Hz

Ring Tone: UK Standard

Ring Voltage: Set to HIGH (HT801 supports up to 90V)

Loop Current: Set to 18–20 mA

Polarity Reversal: NO (Virgin does not use it)

Current Disconnect Threshold: 900 ms

The AI advice is that these settings make the HT801 emulate a proper BT exchange line, which B&O base stations expect.

Does this sound plausible?

It also begs the question  - Can the VM Hub FXS Port not be so configured?