ID this bird by call description?

There is a bird I'm hearing this year in Austin, Texas, that I don't remember before. It starts with a very fast chirping (about 10 - 15 of these, but it's so fast I have a hard time counting!) and gradually slows down. This call just lasts seconds...then a pause...then it goes again about 2 more times before being quiet for a while. I wish I could see it better, but it's a nondescript bird...just brown and small. Could it be a local mockingbird that has learned a new call?? Or another bird?

Thanks!
Connie in Lakeway, Tx (20 miles out of Austin on the lake)

Might be some type of Wren too. Maybe Bewick's?

http://www.allaboutbirds.org/guide/Bewicks_Wren/id

Thanks...I'll go look it up. Does the Internet have a place where I can LISTEN to bird calls or songs? I looked the other day when I first heard this bird, but couldn't find a free place to listen! ;-)

No...I went to the site you gave me (LOVE IT! You answered my question with that site!!) and although THAT call is BEAUTIFUL, it's actually more complicated that the one I hear!

Possibly a Chipping Sparrow you may be hearing. http://identify.whatbird.com/obj/237/_/Chipping_Sparrow.aspx

Burd...this is the closest yet, but still not it. Those calls all sound a bit "irritating" to my ears, and this bird's call is beautiful! I could listen to it all day! But thanks!!

You may also want to try House Wren.

Here is the House Wren

http://www.allaboutbirds.org/guide/House_Wren/id

The "long, jumbled bubbling" is correct, but it's longer and the beginning chirps are NEVER there..??

Thanks anyhoo ("Hoo...hoo" says the owl!! ;-)