Slight humming is often normal for 4K models due to XPR technology. For other noises, check fan settings and power stability.
Identify Normal XPR Noise (4K Models): 4K UHD projectors use XPR pixel-shifting technology, which produces a subtle high-pitched hum during operation. This is normal and not a defect.
Adjust Fan Settings: Go to [Menu] > [Settings] > [Fan Mode] and toggle [High Altitude Mode] to see if the noise changes with fan speed.
Try Eco Mode: Switch the lamp power to [Eco Mode]. This often reduces fan noise and electrical humming.
Power Stability: Plug the projector directly into a wall outlet. Low-quality power strips can cause electromagnetic noise (Coil Whine).
Clear Ventilation: Ensure there is at least 50cm of clear space around the vents to prevent the fan from overworking due to heat.
Note:
Warning: If the noise is accompanied by a burning smell, heavy vibration, or grinding sounds, power off immediately and contact ViewSonic Support.