I managed to get my hands on a Beocom 1401 phone (or it might be a 1500, not sure what the difference is), which includes the 'Table Holder A/V', with the volume controls for video and audio. The phone works fine, but the volume buttons do not.  Got it for £13 on eBay and there's not a mark on it, so it was a real bargain. The table holder is not connected to the phone line in any way, so surely it must have batteries in order for the volume buttons to work, but I cannot find anywhere for checking/changing the batteries!  Under the little flap where the notepad goes? No.  Beneath the metal piece behind the handset, which comes off with some difficulty?  No. The manual on the B&O site for this phone makes no mention of the A/V base either.  Anyone have any experience with it?