Bunching when reversing?

What is the best way to get my machine to stop bunching the fabric when going in reverse (locking the stitch).  I've tried adjusting the pressure on the foot, but it's happening almost every single time.  I just upgraded to a Janome Memory Craft 6500. 

Oh, I'm also new here!  Glad to have found a nice sewing forum.   

Thanks in advance!

Are you using a new, sharp needle? If so, then it may be one of those machines in which you have to hold the thread ends towards the rear of the machine for those first few locking stitches.
Another suggestion is for you to start about 1/2" down into your seam and begin in reverse to the top of the seam, then continue the rest of the stitching line. This way, your machine has a better grip of the fabric and hopefully will not bunch as easily.