try maybe some plain good ole' black oil sunflower seed? i don't know of the birds of texas, but i do know that BOSS is a favorite of many lovely birds.

also, consider maybe offering something a little different. maybe an orange sliced speared to a conspicious branch, or grape jelly. here in the northeast we have orioles and such. i'm sure there is something in Texas that will enjoy that! i've also read that woodpeckers enjoy the flesh of oranges. shelled peanuts are also very popular among birds here, and almonds, pecans, and walnuts.

good luck! i hope i've helped!

If you're still monitoring this thread, here's what I use in DFW.
Avoid mixed seed with corn products and red millit. Those attrack the grackles and pigeons the best.
Use black oil sunflower, safflower, white millit, peanuts, and suet cakes (chickadees love suet).
THe best way to attract the desireable birds to your yard is to have a good landscape with different levels (short plants, medium plants, understory plants and trees. Add a water source - birdbath, pond, fountain with moving water. Grackles and pigeons like to eat off large expanses of grass - the better birds like a more woodlandy setting. If you can provide that, you will get the biggest variety.