Holes in my Garter Stitch!

[ScandaKnitvian]

I'm not sure what I'm doing...but every once in a while...maybe every 10 or 15 rows or so...I'll have a "hole" in my garter stitch. There's NO loop sticking out as if I've dropped a stitch...but there is a definite hole and I can't figure out why. When I look at the stitches, it definitely looks like one stitch is "missing". I cannot figure out what I'm doing to cause this. I'm not sure how to post a picture, and anyway, I frogged back and re-knit the place with the hole.

Any ideas???

Patty

[sfavereau]

Could it be when you are setting down your knitting, you are picking it up with the working thread on the wrong needle?