Very good Phil,
We now know for sure that the problem is with the line driver in the France Telecom Exchange which we had both really thought was the case from the begining. So we must both wait another 7 days for this more senior engineer hopefully to change the line driver.
What your tests also show is that whilst the fault is at the exchange, the BeoCom 6000 does draw more line current than most other makes of phone because even with the faulty exchange line driver, the voltage drop is greater with the Beocom 6000, this is basic Ohms law in a DC circuit which is Volts = current x Line resistance where line resistance is normally constant..
Looking forward to hearing that the problem is fully solved in 7 days
Keith..
Location: Hampshire, England