Pink screen of death - dual recording on 622 :o(

I've had this occur a couple times recently, and wonder if anyone else has had this problem....and maybe a solution.
What happens is; when I have 2 shows recording simutaneously (via both tuners on the 622 machine), one will record only a pink screen.
I caught a show, half way thru, and had to stop recording the other program to get video back on the other.
I have successfully recorded 2 shows at once many times in the past, but this PS of D has happened twice in a couple weeks now.