My experience with updating to version 8.0 left my TZTL12F with some problems. I never updated since I bought the displays in 2016. My update with the 8.0 software files left my equipment at version 5.06. It started at version 2.0. I followed the instructions exactly. I even downloaded new software to new microSD cards, 8 gb from Sandisk. It just will not update to 8.0. Even worse now, the internal sounder, set to TZTL12F will not display the fishfinder data, it only gives the depth. Has anyone else had a similar problem and any luck to fix it? I would really appreciate some feedback. Tech support solution so far was to download the files again and try again. Thanks for any input.