Uh oh, your home router is making weird hissing or buzzing or clicking noises and you’re worried something is amiss. What’s going on with your router?
Home routers are usually quiet, fanless devices, but solid state electronics do sometimes emit noise due to electronic resonance of certain frequencies, overheating parts, firmware, poor hardware quality and poor device placement.
How Your Router Makes Noise
Routers generally have few moving parts, so that limits the source of the noise to a few options:
- Internal fan
- Overheating parts
- 5GHz network noise
- Vibrations due to other devices
- Vibrations due to router placement
- Broken or cheap parts or poorly designed hardware
Troubleshooting Why Your Router Makes Noise
- Internal fan: If your router has a fan and the air intake vents are blocked. Clear the vents of dust or move the device so it has unblocked airflow away from a wall or other object.
- 2.4GHz or 5GHz: If your router is dual band and broadcasting both signals, sometimes the 5GHz band will emit interference noise.
- High-speed internet: If your internet speed is fast, over 400mbps, your router will be handling lots of data and will be more powerful than a router that routes data over a lesser connection, like 25mbps.
- Coil whine: A whirring noise can happen when Wi-Fi is in use and therefore drawing power. As the coils are part of the power conversion circuitry, they get loaded and as they’re imperfect components, you get whine due to internal vibrations.
- Overheating parts: This is related to the fan, but sometimes having too many devices connected to your router can overload the router’s stability. Make sure the router can handle the load.
- Also, check your router’s signal emission strength — if you live in a space less than 500 sq ft, there is no need to have the router constantly emit a signal at full strength.
- Old router: routers are mostly circuitry and non-moving parts, so a noisy router could indicate something has come loose or is about to fail: capacitor, coil, or a crack in the circuit board or failing power supply. [Thinking of buying a used router? Do this to keep your data and privacy intact.]
- Resonance: is your device near something else emitting a similar frequency?
- Poor placement: This is simple and obvious, but sometimes the router is sitting on something that vibrates. Move it away from other electrical devices.
- Poorly designed hardware: Constant loud hum is common in Technicolor CGM4141 Docsis 3.1 Panoramic modems; if you have a Pano 3.1 modem from Cox, be prepared to endure a router emitting a humming noise. This is a known issue for this hardware.
What to Do to Stop the High-Pitched Hissing, Buzzing or Other Noises Coming From Your Router
Inspect the router and determine if the sound is there all the time or under which conditions create the noise.
If the problem is a loud fan: updating the firmware could solve overheating problems that lead to constant loud fan noise. If that doesn’t quiet your router, you might need to add a cooling element (attach a cheap heatsink to it with some thermal paste), or buy a new router.
If fanless, is the router overheating? See if there is a firmware update for your router that fixes this problem. If this is a new problem that occurred after updating the firmware, revert to the old firmware version, or consider utilizing open source firmware like https://dd-wrt.com/.
Noise when streaming video: If the router is making an intermittent humming noise whenever someone connected to the router is watching a YouTube video or streaming lots of data, with either the 2.4GHz and 5GHz signals, they easiest solution could be to put the router somewhere cooler, or with more airflow. It could also be a hardware problem, as follows.
- If you suspect that the high-pitched noise is is coil (or transformer) whine, it is impossible to tell if it will fail completely or last forever despite the sound. Open the case and try to pinpoint if the source of the whine is caused by the coiled wires (or transformer plates) vibrating. If the offending device can be determined, a small dab of epoxy resin can often stop the vibration. Note the cure time of the epoxy, and give it time to thoroughly cure before using the router.
Coil or other element: If you notice the noise when the WiFi network is on, the culprit could be a vibrating coil. Power amplifiers when the Wi-Fi is on, end up drawing a lot of power when they’re in use, which in turn means more power goes through the coils.
Bad capacitor: Routers are made with cheap capacitors these days, and given the work they are expected to do, inductors are almost saturated on load. This can cause harmonics to go wild across all ranges, and create high-pitched whining noises and function disruptions:
- “Large numbers of tantalum capacitors and aluminum electrolytic capacitors have conventionally been used in electronic equipment, but are now being replaced with cheap ceramic capacitors thanks to product downsizing and reliability issues. As electronic equipment becomes more multi-functional and quiet, the ‘acoustic noise’ caused by ceramic capacitors, which was not formerly noticeable, has become a major design issue in the power circuits of various devices, such as laptop computers, mobile phones (smart phones), DSCs, and flat-screen TVs.” – MLCC Capacitor Solutions
- Helpful link to identify bad capacitors: https://console5.com/wiki/Identifying_Bad_Capacitors
Router 5GHz Noise [Fix]
If the problem is most noticeable when connecting to the 5GHz band, then disable your router’s 5GHz network.
- First reset the router by pressing or holding the “reset” button for 10 seconds. Once it reboots, is the sound problem fixed? If not, disable the 5GHz frequency and use the 2.4GHz connection.
- To disable the 5GHz network:
- Make sure your computer is connected to your router network. Wired or wireless is fine.
- Open your browser, and type 192.168.1.1 (or whatever your router admin IP address is — find it on the bottom of your router) into your address bar. Press enter.
- Fill in your username and password for your router.
- Find the Settings tab, or similar page.
- Look for Wireless or WLAN to change your wireless settings.
- Select the “5GHz” setting and disable it, or unsync it from the 2.4GHz band.
- Apply your changes, save and reboot the router.
