Hello chrisl,
Check the power source that the printer is plugged into. Try plugging the printer directly into a another, known-to-be-good, wall outlet as a test. If too many devices are using one circuit breaker, temporary brownouts can occur at the printer. The printer can either suffer print quality problems, or drop power and reinitialize.
Make sure that you have validated that your power source is stable, and if possible monitor the line voltage. Avoid plugging the printer into a UPS (uninterruptable power supply or surge protector), especially if you are not sure of its power rating.
John
Phaser 4510 display is blank even after multiple power off and wait attempts