I'm thinking this is a fledgling Red-winged Blackbird that hasn't grown feathers on its face yet. Like this: https://www.flickr.com/photos/feltonphoto/7324816742
Before I listened to the recording, when I read "but it seems it is something else that shares the same habitat" I immediately thought Field Sparrow. Sure enough it is the Field Sparrow's bouncing ball song. ?
Yes, no stripes as in malar stripes and they also lack the streaking on the breast and flanks. Savannahs are not as boldly patterned above - they are a more uniform brown color on the face and wings.
I don't think it sounds like a Ruby-crowned Kinglet - they make more of a "ch-cha ch-cha" sound. They shouldn't be in Texas right now anyway (assuming this was heard recently).
This appears to be a juvenile Savannah Sparrow. Field Sparrows have very plain gray faces, lighter orange caps, longer tails, and no streaking on the flanks.
@Administrator I noticed that after a rather short period of time we are not able to edit our posts. It would be great if that could be changed, maybe remove the edit option after a few hours or days rather than minutes or make it so we can always edit our posts like before.