Nacho! Ah, it is so good to see her so big. 
They do vocalize, but I have to say it is a bit unusual without any other geckos around. Usually with a solitary gecko it is a warning that they are annoyed with handling or cleaning or the like. On the other hand, knowing the history and spunk of this girl, she could just be making her presence known!
I agree with the other poster, check your temps and make sure there is a good warm side and you've got both a moist and dry hide. Leos can get respiratory infections and it is about this time of year when the temps get colder that it is a good thing to watch for. Just to make sure this is a "bark" and not a "cough."
As for substrate, reptibark is a big no-no. These are desert dwelling herps who don't like splinters. Sticking with papertowels is an excellent choice and we use it around here for all the geckos. Another good option is repti-carpet - I would recommend getting two pieces, it is easier to have a clean one to put in and then wash and dry the other in the meantime. A third and a bit harder on the cleaning scale is unglazed tile. (Glazed tile has lead, FYI.) This is closest to "natural looking" in some people's opinions, but then you have to deal with the bathroom somehow and you may have to get a stronger UTH because tile absorbs so much heat, but does radiate it nicely, being rock and all. Some people do a little of both and tile the floor and then put one folded paper towel in the bathroom.
Hope this helps!
