HP800W Dropping out Yellow part way through print

[CSPrint]

Hi All!
I am printing on a clear static cling material with my HP 800W, using a 32 pass mode with white on the bottom and color on top. We started to notice on longer jobs that go over an hour, that just the yellow drops out. I assume it is some sort of in restriction or air in the line cause all yellow drops out, not just one of the two heads. I tried printing a huge yellow rectangle in a 6 pass mode to see if i could get it to drop out, but it did not. I definitely used more yellow ink in the 6 pass mode image than the 32 pass mode. Any one experienced a similar issue? Any thoughts on where to start looking to fix this?

I attached the picture of the static clings we print and you can see yellow drop out and everything just look magenta. And then i attached a picture of the large yellow rectangle with no dropout.

Thanks!!
Steve

 

[balstestrat]

How much usage on the yellow-magenta printheads?
As a workaround you could try to use spit bars on the side. See if it helps or not.

There is a static dropout issue with optimizer on older units... I wonder if you have the same issue on yellow.
Do you have this metal on the right side of the drive roller? If not, maybe consider asking HP for it.

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