Firstly what sized basket are you using? Don't botther with the 7g basket it's hopeless.
Secondly I don't doubt you have a consistant tamp style as you are consistantly getting coffee out of the left spout. Check that you are not consistantly slanting the tamp one way or the other.
Is the Anfim Best a stepped adjustment grinder? Supposing that the single adjustment to coarser is causing too fast a flow the only way to compensate is to updose a little and slowing the flow that way.
Hope that helps.