First noted about 0550 UTC, when I was awaiting Voice of Nigeria at the nearby frequency of 7255. Strong signal seems to indicate North American origin. Went to bed, woke up by 1230 UTC, and it's still on, and is still there as I write this (1354 UTC). Presumed RNZI underneath this signal, but nothing strong enough to tell. This isn't Radio Habana Cuba, but what it might be, I can't say.
UPDATE 1359: Possible Radio Martí ID. QRT at 1400. RNZI now coming through unhindered.