Humax DRT 800 Remote not working

Have had the Humax drt800 for several years. This past year the remote has started to give me problems. It would work great for days on end, then would get a night of double/tripple clicking to get to work and now finally the remote does not work at all. I have 2 of these Tivos, so I have 2 remotes. My other Tivo works fine and so do both remotes. I replaced the IR Sensor with a TSOP 1156 and that did not fix it. I have a TSOP 2156 that I have not installed yet. Did I do something wrong? Was this the wrong sollution? What is the sollution? I can't seem to figure it out. Please help.