Projectors are designed to allow users to easily switch between different input sources. However, there are cases where a projector may change inputs unexpectedly without any user interaction. This can be frustrating and disruptive during a presentation or when watching content.

So, what are the reasons behind the “Projector Input Changes by Itself” issue and their solutions?

This can be caused by a variety of factors, such as automatic input switching, power ground issues, signal loss or change, and infrared interference. Fortunately, there are several solutions available to prevent projector input changes, such as disabling auto-source switching, addressing power ground issues, maintaining a steady signal, and blocking IR sensors.

In this article, we will explore these causes in more detail and provide tips on how to prevent your projector from changing inputs by itself. I am sure you will have a possible solution to this problem.


Projector Input Changes by Itself – 4 Possible Reasons

There are several reasons why a projector might change its input source without user intervention:

  • Automatic Input Switching
  • Power Ground Issues
  • Signal Loss or Change
  • Infrared (IR) Interference

Reason 1: Automatic Input Switching

Some projectors have an auto-source switching feature that automatically detects and switches to a new input signal when it becomes active or the current input signal is lost. While convenient, this can cause problems if the switching occurs unexpectedly. There are a few reasons why auto-switching may change inputs without user action:

New signal detection

The projector detects a new active input and automatically switches to display it.

Current signal loss

If the projector loses the sync or input signal it is currently using, it may switch to another input.

Reason 2: Power Ground Issues

Projector Power Ground Issues

Differences in power potential (voltage) or power line noise can interfere with a projector’s functionality and cause input switching. This is more likely when equipment is plugged into different power panels.

Power potential differences

Variations in voltage between power sources can disrupt the projector’s operation and change inputs.

Power line noise

Interference or unclean power in the lines can introduce errors that switch the projector’s input.

Reason 3: Signal Loss or Change

Interruptions or instability in the signal connection between the input source and the projector may cause the input to change as the projector attempts to find a viable signal. A few potential signal issues include:

Temporary signal loss

The input source temporarily loses synchronization with the projector, causing it to switch inputs. This can happen when a computer changes display modes.

Unstable signal

A weak or unstable connection, like a loose cable, can cause signal interference that triggers the projector to change inputs.

Reason 4: Infrared (IR) Interference

Projectors that use an IR sensor to receive commands from a remote control can have their inputs changed due to stray IR signals from other devices.

Unintended IR commands

Errant IR signals may be interpreted by the projector as commands to change inputs, switch modes, or activate other features.

IR reflection

Reflected IR light from the projector’s own remote can trick the sensor into thinking a change input command was received.

Solutions to Prevent Projector Input Changes

Solutions to Prevent Projector Input Changes

To prevent your projector from changing inputs by itself, consider the following solutions:

  • Disable Auto-Source Switching
  • Ensure Steady, Interference-Free Signals
  • Block IR Sensors
  • Eliminate Electrical Interference

Disable Auto-Source Switching

If your projector allows you to disable the auto-source switching feature, this is the best way to manually control input sources. In the projector’s settings menu, look for options like “input switcher”, “auto search”, or “source search” and turn them off. 

This will prevent the projector from automatically switching between inputs and allow you to manually select and switch between sources using the projector’s controls or remote.

Ensure Steady, Interference-Free Signals

To prevent signal loss or interference that could trigger input changes, ensure all sources are properly grounded and cables are high quality.

  • Check that all equipment is plugged into the same surge protector or power strip and that the protector is grounded. This equalizes any voltage differences between devices that could cause signal interference.
  • Use high-quality, shielded cables to connect sources to the projector. Standard cables can transmit interference and cause signal loss.
  • If using a computer source, set display settings to “clone display” or “mirror display”. This transmits a steady signal even when the computer’s mode changes.
  • A signal processor or video splitter can also help boost and stabilize signals to the projector.

Block IR Sensors

If outside IR signals seem to be interfering with the projector, temporarily blocking its IR sensors can prevent input switching.

  • Cover all IR receivers on the projector with opaque tape or stickers. Make sure no sensors are left uncovered.
  • As an alternative, you can place a cardboard box or other barrier over the front of the projector when it is not in use to block all IR signals.
  • Be sure to remove any IR sensor blockers when you need to use the projector’s remote, as the sensor is required to receive commands from the remote control.

Eliminate Electrical Interference

To rule out interference from power sources, have an electrician inspect your connections and wiring.

  • As mentioned above, make sure the projector and all source devices are properly grounded to the same ground connection. Different ground potentials can transmit interference through connected cables.
  • Check that the projector and sources are on the same circuit or different circuits with a common ground. Circuits with a shared ground are less likely to create interference.
  • Ensure wiring is separated for power and data cables. If wiring is bundled together, interference can pass from power to signal cables.
  • Protected power strips or UPS battery backup units can also help filter out power line interference before it reaches connected devices.


There are several potential causes for projector input changes, including automatic input switching, power issues, signal problems, and IR interference. The best solution will depend on the specific reason for the problem. However, the most effective solutions are usually disabling automatic input switching, ensuring all equipment has a common stable power source and ground, using high-quality shielded cables, blocking IR sensors when the projector is idle, and eliminating any electrical interference in the wiring.

If you methodically troubleshoot the factors that can cause unwanted projector input changes and implement the appropriate fixes, you should be able to prevent interruptions and ensure your projector only changes inputs on your command.


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Fernando Shrader

Hey, It’s me, Fernando Shrader. I’m the creator of this website. You might wonder why I’ve created this blog and what’s the difference between Visual Finds and other online blogs. As a professional technician working for the last 8 years with projectors, I though this is the right time to share what I’ve learned in this journey with an online audience so they can see what I’m doing and how they can solve their problems! Happy Learning!