According to the docs at
http://www.cisco.com/en/US/prod/collateral/voicesw/ps6788/phones/ps379/ps6513/product_data_sheet0900aecd802ff012.html there is a hearing aid compatible handset available for Cisco phones. (Implying, to me, it's an optional extra)
However, it's not listed as an accesory at the bottom of the page.
http://www.cisco.com/en/US/prod/collateral/voicesw/ps6788/phones/ps379/prod_bulletin0900aecd8025f09b.html says all handsets are hearing aid compatible.
What gives ? Which page is right ?
All Cisco 7900 series phones are HAC We have quite a number of Hearing Impaired users
that have used 7900 series quite successfully but on occasion we have used in-line amplifiers
If you need some further clarification try;
Any suggestions for troubleshooting hearing aid/phone problems ? I've got a user who claims their hearing aid isn't working with the Cisco phone (Or is it vice-versa ?)
These are, of course, very tricky situations
Can you find out from the user what make/model of Hearing Aid
they are using? And what they mean by not working? Is there
feedback, too loud, too quiet.....if they have any problems with their
home phone etc. etc. you know the drill.
It's possible that there may not be a workable solution in the 7900 series. For one
of our users, a lady with MS, we had to actually purchase a special analog phone
and connect her to a VG to achieve the desired results.
If you let us know some further info hopefully we can help you find something that works.