I don't hear voices, only music

For the past few weeks, I've been waking up with songs in my head. Even before I could say a word to anyone -- even before getting out of bed -- I would hear the melody (melody first, then lyrics) playing consistently, as if I had been singing them along with the artist. The songs change each day, mostly, and I often don't remember these songs throughout the day. But, a large portion of my getting-ready routine is punctuated with me blurting out random phrases from these melodies playing through my mind. A few days ago, I kept waking up to the sound of Avalon's "Testify to Love."

I don't know what this means, because I certainly don't fall asleep listening to these songs. There must be a trigger hidden somewhere deep, and when I sleep, these melodies are called to the front of my mind. These haunting melodies are shifting through my gray matter, firing through my synapses, pulsating in different beats and notes, ever-ready to spring out of my mouth when my eyes open. Some mornings, I wake up and walk to the bathroom and already I was hearing Aguilera's "Hurt" playing in my head.

This recent development makes me wonder if I'm getting enough rest. Obviously my brain is at work more than usual if I'm waking up to the chorus of a Nickelback song vibrating in my head. What does this mean, then? Am I getting relaxed enough and is my body resting enough to get recharged? Is it abnormal to wake up with an automatic radio in your head? I'm not likely to believe that it's a cheery disposition that allows me to sing in my head like a crazy lunatic (or aspiring American Idol contestant). Does anyone have any suggestions? Dream interpreters, any advice? Freud? What say you...?