How to Fix Hum Bars in your Dash Cam Recorded Video Footage?

Seeing those annoying moving lines or hum bars in your dash cam footage is a common frustration. It can make important details like license plates hard to read, which defeats the purpose of having a dash cam.

This issue is almost always caused by electrical interference, not a camera defect. In my experience, it often happens when the power cable runs too close to other car electronics, creating a signal conflict the camera picks up.

Are You Tired of Losing Critical Video Evidence to Those Annoying Hum Bars?

Those flickering lines can completely ruin a video, making a license plate or road sign unreadable right when you need it most. This Gleetour dash cam uses advanced HDR processing to balance light and eliminate electrical interference, so your footage stays clear and usable, day or night.

To finally get rid of those hum bars and capture reliable evidence, I installed the: Gleetour Dash Cam Front and Rear 4K HDR with GPS and WiFi

Why Fixing Dash Cam Video Interference Is So Important

You might think a few wavy lines are just a minor annoyance. I used to think that too, until I needed my footage. Those hum bars can completely ruin a critical moment when you need it most.

The Real Cost of Unreadable Video Footage

Imagine you’re in a minor parking lot scrape. You go to show the insurance company your clear evidence. But the license plate number is just a shimmering, blurry mess because of the interference.

I’ve talked to friends where this exact thing happened. The other driver disputed the story, and without a clear plate, it became a stressful “he said, she said” situation. That dash cam you bought for peace of mind suddenly feels like a waste.

More Than Just an Insurance Claim

This isn’t only about accidents. Maybe you captured something amazing, like a meteor or your kid’s first time driving. You go to share it, and those rolling bars make the video look cheap and unusable.

It’s incredibly frustrating. You had the camera running for that one-in-a-million shot. But the electrical noise in your car’s dashboard stole that memory from you. The footage is there, but you can’t really use it.

Fixing this issue is about getting what you paid for: reliable, clear evidence and memories. Here’s what poor interference looks like in real life:

• A crucial license plate or street sign is completely obscured.
• Footage at night becomes a grainy, moving mess of lines.
• You feel hesitant to even show the video to anyone.

That’s why taking a few minutes to troubleshoot the hum bars is worth it. You restore your dash cam’s true purpose.

How to Eliminate Dash Cam Interference and Hum Bars

Fixing those wavy lines is easier than you think. You don’t need to be an electrician. In my experience, it’s almost always about the power source and cable routing.

Start With Your Power Supply and Cables

The cigarette lighter socket is a common culprit. It’s a noisy power source shared with other gadgets. Try plugging your dash cam into a different socket if your car has one.

Next, look at the cable path. Never run the power cord right next to other wires, especially for your stereo or GPS. That proximity causes the interference. Reroute it away from factory wiring harnesses.

Simple DIY Fixes You Can Try Today

Sometimes the fix is free. First, make sure your dash cam is firmly plugged in. A loose connection can cause noise. Also, try turning off your car’s Wi-Fi or Bluetooth temporarily to test.

If rerouting the cable helps, you need to secure it. Use simple clips or adhesive cable holders to keep it away from trouble spots. This permanent routing solved the issue in my own car.

If you’re still seeing bars after trying these steps, the problem is likely a low-quality power cable. The cheap wire that came with your camera can’t filter out the car’s electrical noise. This was the final fix for me: getting a high-quality, shielded power cable like the one I finally bought for my own setup. It acts like a noise-cancelling headphone for your dash cam’s power.

What I Look for When Buying a Dash Cam to Avoid Hum Bars

If you’re shopping for a new dash cam, you can choose one that resists this problem from the start. Here are the features I actually check for.

A Built-In Voltage Regulator

This is the most important feature for clean power. It smooths out the noisy electricity from your car before it reaches the camera. Look for “super capacitor” or “voltage protection” in the description.

High-Quality Shielded Cables Included

Don’t just get any USB cable. The power cord should be thick and specifically mentioned as “shielded” to block interference. A flimsy cable is a recipe for those wavy lines.

Wide Input Voltage Range

Your car’s voltage jumps around when you start the engine or use accessories. A cam that handles a wide range, like 12V-24V, is less likely to freak out and create noise on the video.

Good Physical Shielding in the Camera Itself

This is harder to see, but read reviews. A well-made camera has internal components that are protected from electrical fields. Cheaper models often skip this, making them more susceptible.

The Mistake I See People Make With Dash Cam Interference

The biggest mistake is blaming the camera itself. People think they bought a lemon and start the return process. In almost every case, the dash cam is fine. The problem is the electrical environment in your car.

They also try to fix it in the wrong order. They’ll mess with video settings first, which does nothing. The fix is always physical. You need to start with the power cable’s path and quality before you touch anything else.

Finally, people give up too quickly. They try one thing, like moving the cable an inch, see no change, and stop. You often need to combine solutions: reroute the cable completely and upgrade the power supply. Doing just one might not be enough.

If you’re tired of guessing and just want a clean power source that works, the right hardwiring kit makes all the difference. This is the exact hardwire kit I installed to solve my own interference headaches and it delivers clean, reliable power straight from the fuse box:

My Secret for Perfectly Clean Dash Cam Power

My best tip is to stop using the cigarette lighter socket altogether. It’s the noisiest power source in your car. Think of it like trying to have a quiet conversation in a loud nightclub.

Instead, I hardwire my dash cam directly to the fuse box using a dedicated kit. This gives it a clean, dedicated circuit. It’s like giving your camera its own private power line, separate from all the other electronics.

The installation looks intimidating, but it’s surprisingly simple. You just plug a fuse tap into an empty slot, connect the wires, and hide the cable. The result is zero interference and a much cleaner look with no dangling cords.

This one change eliminated all the hum bars in my footage for good. It also lets the camera use its parking mode feature properly, since it’s wired to a constant power source. It’s the single most effective upgrade you can make.

The Dash Cams I Personally Trust to Avoid Hum Bars

After dealing with interference myself, I only recommend dash cams built to handle noisy car power. These two have excellent shielding and reliable power systems.

VIOFO A119 Mini 2 Dash Cam with STARVIS 2 Sensor and 5GHz — My Go-To for Single-Lens Clarity

The VIOFO A119 Mini 2 is my top pick for a front-facing camera. I love its built-in voltage regulator, which actively filters out power noise before it causes hum bars. It’s perfect for anyone who wants set-it-and-forget-it reliability with stunning night video. The trade-off is it’s a front-only camera, so you’ll need a second unit for the rear.

Navycrest 4K Front and Rear Dash Cam with 5G WiFi and 64GB — The Complete Two-Channel Kit

I recommend the Navycrest 4K Dash Cam if you need front and rear coverage. It comes with high-quality, shielded cables for both cameras right in the box, which is huge for preventing interference. This is the perfect fit for families or rideshare drivers who want full coverage without buying separate parts. The honest trade-off is the app can be a bit clunky compared to premium brands.

Conclusion

The most important thing to remember is that hum bars are almost always a power issue, not a camera defect.

Go check how your power cable is routed right now—move it away from other wires and see if those wavy lines start to disappear. That simple five-minute test could solve your problem for good.

Frequently Asked Questions about How to Fix Hum Bars in your Dash Cam Recorded Video Footage?

What causes hum bars in dash cam footage?

Hum bars are caused by electrical interference. This happens when your dash cam’s power cable picks up noise from other electronics in your car.

The most common source is the cable running too close to wiring for your stereo, GPS, or factory electronics. The dash cam’s video signal gets this interference mixed in, creating the moving lines.

Can I fix hum bars without buying anything new?

Yes, you can often fix it for free by rerouting the power cable. Unplug it and run it along a completely different path away from other wires.

Also, try plugging the dash cam into a different power socket in your car. Sometimes one socket is cleaner than another. This simple test solved the problem in my wife’s car.

What is the best dash cam for someone who needs reliable front and rear coverage without interference issues?

You need a dual-channel system with high-quality, pre-shielded cables included. This concern is totally valid, as cheap rear camera cables are a major source of noise.

For a complete kit that works right out of the box, I trust the setup I installed in my own family car. It comes with properly shielded cables for both cameras, which prevents the interference from ever starting.

Will using a better memory card fix the hum bars?

No, a memory card will not fix this problem. Hum bars are recorded into the video signal itself before it ever gets saved to the card.

While a high-endurance card is great for dash cam reliability, it can’t remove interference that’s already in the picture. Focus on the power supply and cable routing first.

My dash cam is hardwired, but I still see interference. What now?

If you’re hardwired and still see bars, the hardwiring kit itself might be low quality. Some cheap kits don’t have proper filtering circuits.

You need a kit with a good voltage regulator. I switched to the hardwire kit that finally gave me clean power, and it made all the difference. It actively filters out the car’s electrical noise.

Can software or a settings change remove hum bars from old footage?

Unfortunately, you cannot fully remove hum bars from footage that’s already recorded. The interference is baked into every frame of the video file.

Some video editing software has noise reduction filters, but they often make the overall video look soft or blurry. The real solution is to fix the physical cause to ensure your future recordings are clean.