No advice here either, I know my SIL said she would ignore DD when she did it but she was over 1 & knew she wasn't getting any attention...so would stop.
It's just part of them finding their voice & often it's squeels of delight so you know they are happy. Charlie started a long time ago & at 6am, ohhhh so annoying & usually takes it up a notch just when wanting to hear something on the news!!
Like Dee said, it will come & go. We thought it was over & all of a sudden "it's baaack"!!!he,he.