Tony, please don't file the mouth. As Warren suggested, rounding the corners of the iron may help a bit.
The other thing is, when's the last time you flattened the bed? If it is not flat, the plane will struggle to take a shaving at all, until you've extended the blade to the point where it will only take a thick shaving. But it can't take a thick shaving because the mouth is too tight, so the problem doesn't resolve.
Install the blade so that it's recessed up into the plane about an eighth of an inch. Seat the wedge as you normally do. Use spray adhesive to attach a piece of 180-220 sandpaper to something flat. Draw pencil lines on the sole at the toe, right in front of and behind the mouth, and at the heel. Abrade the sole on the sandpaper, carefully and without any rocking, until the pencil lines are gone.
In addition to flattening the sole, this process will also open the mouth a bit. The more you abrade the sole, the wider the mouth gets, so don't overdo it.
If you moved from Kansas to Texas and haven't flattened the sole, I guarantee it's not flat.
Let us know how it goes.
"For me, chairs and chairmaking are a means to an end. My real goal is to spend my days in a quiet, dustless shop doing hand work on an object that is beautiful, useful and fun to make." --Peter Galbert