A big problem with YUV 4:2:0 / 4:1:1

[Wizal]

Ok here is the problem :

I capture through a Miglia DC Take 2 DV Bridge using Premiere and Mainconcept DV codec.

In PAL mode everything is fine, but in NTSC mode I end up with a 2x2 color grid, which I would presume is due to problem with YUV 4:1:1 (since the problem doesn't appear in NTSC B&W nor in PAL YUV 4:2:0)

As you can see the frame ends up like this :

[snip]

Which is obviously not right. So I'm trying to find out :
1) What exactly is happening here ?
2) How can I correct it ?

Can any expert assist me ?
Pleeeeeaaaaaasseeee it's driving me mad!

[Koepi]

a) this looks more like 16-bit-dithering than YUV troubles...

b) ...so try setting your desktop bit depth to 32 bit... this can help it (but mustn't necessarily).

Report if this is successful.

Regards,
Koepi

[Wizal]

Desktop is already 32 bits of course.
Besides I don't see why it would affect only NTSC DV files.

I'm almost certain it has to do with 4:1:1 since this is the only difference between PAL and NTSC DV : PAL DV is 4:2:0 and NTSC DV is 4:1:1