I don't know how many of the same features my SQ9000 has, but for my model, here's what the manual says to do to keep the needle in a permanent middle position:
Normally, the straight stitch (left needle position) is automatically selected when the sewing machine is turned on. The machine can be set so that the straight stitch (center needle position) is automatically selected when it is turned on.
Turn off the sewing machine. Hold down the "+" side of the +/- stitch selection key on the left and turn on the sewing machine. After turning on the machine, release the "+" (stitch selection key). The initial needle position changes to the center needle position and will stay that way until you change it back to the left needle position.
Let me know if it works.