Canon imageCLASS MF7280 Printer Manual page 41

Printing garbled text.
Cause 1
Remedy
Cause 2
Remedy
3
Cause 3
Remedy
3-6
Printing Problems
The printer selection you made when you set up or installed your software
application was incorrect.
Make sure the correct printer is selected. (See Chapter 2, "Getting Started," in
the PCL Driver Guide or the UFR II Driver Guide.)
If different portions of the text are garbled every time you print, the interface
cable may be too long, and spurious noise is corrupting the data.
Using a USB cable of 3 meters or shorter is recommended. If your USB cable is
longer than this, replace it with a shorter one.
The machine is plugged into an outlet shared with another electrical device
capable of generating noise, such as a photocopier, shredder or air conditioner.
Plug the machine into a different outlet or consult a qualified technician to install
a noise filter.