Resound phone clip and business phone connection

OK, my 10 or so year old Jabra A7010 Bluetooth Hub that was plugged in between the handset and the phone bit the dust :frowning: And Jabra stopped making them before I even bought mine some 10 or 12 years ago. So I’m looking for a new solution as I hate getting into speaker phone battles. It was so nice being able to mute the mics on my KS6’s and just hear the phone call directly in my aids. So my phone does not have a headphone jack (???), a multi-line Lucent MLX-28D that has been on my desk before I came here in 2002. What is with this USB connector on the MDA200? Where does it connect to? And you mention another cable being needed that is phone specific??? Where do you find out which one you need and how do you get one? Needless to say, Plantronics support wouldn’t even talk to me. “You don’t have a Phonak hearing aid? WE can’t help you.”

HELP!!! Are there other working solutions to get Bluetooth out of an old multi-line office phone???