Getting streaks when printing magenta

Mike, this is classic banding. First of all I would check to make sure your humidity is high enough. Too low RH for your environment will cause this and cause it to keep happening. In my case I keep the RH above 40%. Some people at higher elevations need to keep it higher. Next, I would make sure that the capping area and wiper are clean and free of dried ink. The capping area needs to be clean in order to seal against the head. The wiper can build up rubbery goo that will keep it from properly wiping the head durring the head clean cycle. Always do a nozzle check before printing and understand what a "good one" looks like. It's very simple, fast and a great tool. If the above is taken care of, a regular head clean will usually get all the nozzles firing (see the nozzle check). Since you've had your printer a short time (I'm assuming it's a new machine) you probably do not have major settling in the dampers or clogged filters. It's most likely just on the surface of the head. A wet swab (very gentle press) of the head face will probably get you back to a good nozzle check.

Ian

Welcome to the forum!

My experience has been that lines of color (not blank lines in a color) are caused by ink flowing through the print head and forming a drop on the print head face.

If your ink supply has a build up of pressure for some reason (vent hole plugged or supply elevated too high) it can cause this problem.

It builds until it almost drips, then the drop drags across the surface of the shirt.

If you can locate yourself to have a vantage point where you can watch or see the surface of the print head while it prints, you may be able to see if this is the problem.
Banding from plugged nozzles usually has the symptom of "blank" lines across blocks of solid colors in your graphic.

Hope this helps.