I guess I am late coming to this thread but I wanted to add my 2-bits worth since I was having similar problems. Except mine was much more severe; Dropbox was crashing my modem which threw all devices off the Internet including shutting down my TVs. And I tried over and over to fix it, including going to my service provider (I thought possibly the modem was done) and Dropbox for help. Nothing. Lots of back and forth but no solutions. Then today it started to work properly, with no hint that there was ever anything wrong. And I do see I now have a new version 82.4.155 installed yesterday (2019-10-3) according to Control Panel. WTF? The tech from Dropbox never said a word to me through many emails about a new version. I guess even they don't know what goes on inside Dropbox!!!