Undependable stitches going right to left and down to up

[monakeegan 2]

I have a 4 year old Millie.  She is a great machine except that I cannot rely on getting good quality stitches going right to left or going up.  Is there anyway to avoid this?   It is so consistent in giving me inconsistent quality stitches that I do all I can to avoid stitching in those directions.  But, I don't seem to have these problems with pantographs.  Isn't that weird?  

I keep thinking it is something I am doing wrong.  Hope you have some help for me.

 

[Kueser 46]

Slow down. Check the tension on your quilt sandwich. If it is too tight, the stitch doesn't melt into the middle as easily. Another thing you can do is move the eye of the needle to the 7 o'clock point. Seems to help when going backwards.