I recently dusted off an old FT-2800M that hadn't been used in years and ran into the same issue as reported in #3919. I believe I have a fix that I've attached to the
#3919 page. Getting Mercurial installed and set up to submit a patch seems a bit daunting to me. It was suggested that I post here in case someone else who's already set up for development would like to grab the code from the bug page, review it, and submit it. If not, I may take a stab at getting set up for the correct development process but it may be some time before I'm able to do so.