VP-540 prints are spongy/grainy

Please post a clear photo of the nozzle test print...

 

What kind of image is that?

What is its resolution?

Is it the photo or does the text at the top edge of the photo look normal and fully saturated?

 

I have never noticed that big of a difference in print quality based on humidity.

We are in a location that can have 100+ degree temperature and single digit humidity for a couple months in a row and in the winter, rainy spells that last for weeks with nearly 100% humidity. We don't have any special humidifying or dehumidifying equipment in use. We run a forced air gas furnace and central air in the summer, but honesty don't do anything out the ordinary for humidity. We'll get a little puckering overnight to the end of a media roll due to the shop cooling down and the heat not running as often, but that's about it.

Are you using OEM inks or third party inks?

 

Provided your climate in your shop is at the required temperature and the temperature of the vinyl is at room, you may want to check to make sure your heating settings in VersaWORKS match determine the profile in printer settings.
Could also be a static issue but I am leaning more towards heat and environment

 

I have always used Default Media Settings. Keep in mind the temperature of the room is also important, especially this time of year. You always want a room temperature environment. If vinyl is too cold and you are running it through the printer heaters you will get prints like this.
what media is it? Are you using Roland Ink?

 

Do yourself a favor and spend $20 on a thermometer/hygrometer that you can keep in your print area. At least then you'll know if your humidity is too low/high or just right. But there are other things that can contribute to this and they can all sort of pile up on top of each other to the point that the problem becomes noticeable. Is your carriage in the low position? Are your print heads clean? Have you replaced the cap and wiper in the last 6 months? Are the print temps correct? Is your media at room temp before you start printing? A nearly perfect test print vs. a perfect test print? That's a pretty dark print, so both cyan and black will have cumulative effects on this one. Have you had any head strikes?
Those are the most common things, but there could be others affecting your print quality.

 

How did you make out with this?

 

Did you adjust the Bi Directional setting in the VP menu?
The head height can be a reason also.
Try to print Unidir instead of bidirectional from Versa.

 

She must be out back in the woods...