All still OC'd - I have a few on freq 262 @ 0750 and another lot on freq 281.25 @ 0755 (those seem to be the sweet spots for my rigs).
What is the freq_value setting you're using for 281.25? Also, how did you find these values in the first place? This thread is the only place I managed to find the freq_values for these frequencies over 250.
Someone probably clever (or clever at copying) put them out somewhere, and I put a link to them in the OP somewhere.
Freq 281.25 has a timeout of 14 and freq_value of 1606 (you can play with the voltage to suit your rig ....)