As the desyncs happen so often it is almost guaranteed that they are mod related, on the other hand it should be quite easy to find out which mod it is, remove them one after the other until they no longer occur. You can still load your save file after changing the mods, only mod related entities ...

Hello,

My wife and I have been playing factorio for some time now but after 1 play session (normally 2-4 hours) the next time we attempt to play we suffer from a constant DeSync loop. If I host (more powerful PC) she desync's 4 or 5 times then crashes, if she hosts my pc will continually re-connect ...