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https://www.youtube.com/watch?v=FSOPsRiiOZk

It really appears your filament is deposited unevenly, I mean your filament is being deposited, but the extruder deposits a litte more in some parts then a litte less later, so as your extruded...

Just to be sure, is your heated bed perfectly vertical, as the last appears to be inclinated towards one side.
To be sure, I suggest you use repetier or prontierface and set the cordinates using the...