tv makes a loud clicking sound from the back every few minutes, it's driving me nuts

Diagnosis

The clicking or popping sound you are hearing from your LG 43UR7300PSA is a phenomenon known as thermal expansion and contraction. As the internal components—specifically the LED backlight strips and the main power board—heat up during operation, the plastic chassis and the metal internal frame expand at different rates. When the tension between the rigid plastic housing and the internal mounting points reaches a breaking point, the plastic "slips" or snaps against a screw head or a plastic clip, creating a sharp clicking sound. This is most common in the 43-inch UR series because the chassis is lightweight and uses high-tension plastic snaps to keep the back panel secure. You can confirm this is the cause if the clicking happens most frequently in the first 30 minutes of powering on the TV or immediately after you turn it off. If the sound is rhythmic and accompanied by a flickering screen or a failure to boot, it is an electrical issue; however, random, sporadic pops are almost always mechanical stress from heat.

How to Fix It

To resolve this, you need to relieve the mechanical tension on the rear housing to allow the plastic to expand without snapping.

1. Power down the TV and unplug the power cord from the wall outlet. Wait 5 minutes for the internal capacitors to discharge.
2. Carefully lay the TV face-down on a flat surface covered by a thick microfiber blanket or a foam yoga mat to prevent scratching the 4K panel.
3. Using a Phillips #2 screwdriver, remove the screws securing the rear plastic cover. Pay close attention to the screws located near the bottom vents and the corners, as these are the primary stress points.
4. Instead of tightening them fully upon reassembly, thread the screws in until they are finger-tight, then give them only a 1/8th to 1/4 turn. The goal is for the screw to hold the panel in place without compressing the plastic against the frame.
5. Check the plastic snap-clips around the perimeter. If any feel excessively tight, gently press them inward with a plastic pry tool to ensure they are seated deeply in their slots.
6. Reinstall the back cover and plug the TV back in to test for 60 minutes of continuous playback.

If That Didn't Work

• Check the Wall Mount Torque: If the TV is VESA mounted, the clicking may be coming from the mounting brackets. If the bolts are over-tightened into the chassis, the TV cannot expand naturally against the wall. Loosen the four VESA mounting bolts by half a turn to allow for slight movement.
• Inspect the Power Supply Board (PSU): If the clicking is a rapid, electrical-sounding "tick-tick-tick," it may be a failing capacitor or a relay on the power board. Look for bulging capacitors (tops that are rounded rather than flat) on the internal power board. If found, the board needs to be replaced.
• Adjust Ambient Temperature: If the TV is placed in an enclosed cabinet or too close to a heat source (like a radiator or fireplace), the internal temperature spikes faster than the plastic can handle. Move the TV at least 4 inches away from the wall to increase airflow and reduce the heat delta.
• Disable Energy Saving Mode: Sometimes, aggressive power-cycling of the backlight in "Eco Mode" causes rapid heating and cooling cycles. Go to Settings > General > Energy Saving and set it to "Off" to maintain a consistent temperature.

Heads Up

• Never use a power drill to tighten the back screws; the plastic threads in the UR7300 series strip easily, which will cause the back panel to rattle.
• Avoid using canned air directly into the vents while the TV is hot, as the rapid cooling can trigger more loud popping sounds.
• If you notice a burning smell accompanying the clicks, shut the unit down immediately, as this indicates a failing voltage regulator rather than thermal expansion.
• Always ensure the TV is completely powered off before removing the back cover to avoid shorting the main board.