Curiouser and curiouser...
Maybe this will help: I first heard the signal hidden underneath WWCR, which was on 3215 kHz at the time. I narrowed the bandwidth on my receiver (which is about all I can do on my basic setup), tuned it around 3223 kHZ, and heard a blues song playing. I assumed it was a normal broadcast station, but knew it wasn't WWCR, and assumed it wasn't North Korea, which broadcasts at 3220 at the same time. After the blues song was some pop song I had never heard before, followed by a punk song. This is when I started to suspect pirate. Then there was a rap-rock song, then a Crystal Method song.
As I stated above, there might have been a station ID around 0351 UTC, but I couldn't hear it.
After that, a movie started. I mean like a whole movie, like the broadcaster just decided to leave the mic next to his tv. I couldn't figure out what the movie was; it sounded like an extremely crappy B-Movie. This lasted till 0510 UTC, when I called it quits. The movie was still playing.
I wonder if it was someone close by just farting around? Did nobody else hear this signal?