If you have tweaked her nights, and it is making no difference, then I would think your next course of action is to tweak the nap and shorten it, or consider dropping it altogether. I am also going through this with my DD who is 2 years and 6 months. She spends lots of time talking and babbling in her room at nap time, and although nights are unaffected so far, I am about to start shortening her nap, which makes me really, really sad because Mommy NEEDS that time, kwim?