If you've noticed some weakness in the strength of your Wi-Fi signal, a U.K. agency suggests it might be linked to your holiday light display.

U.K. communications regulator Ofcom launched an app called Wi-Fi Checker, where users in Wales can test the strength of their Wi-Fi signals. The agency notes several factors can help or hurt your Wi-Fi, including "Christmas fairy lights."

The reason? The lights can cause electrical interference that interrupts Wi-Fi signal strength.

But before you rush to unplug your tree or outdoor lights, keep in mind electrical interference can come from multiple sources including lamps and microwave ovens. Cordless phones and baby monitors can also hurt your signal, hogging the same wireless signal as your router. Not to mention there are other bigger issues affecting Wi-Fi signal, including where your router lives at home.

Concerns over holiday lights hurting Wi-Fi aren't new. In 2009, according to a report from The Telegraph, internet service provider Talk Talk claimed complaints from customers about slow Wi-Fi were linked to interference from Christmas lights.

"Although it might sound silly, interference from domestic lighting and wiring is a major problem across the industry, and at this time of year Christmas lights tend to aggravate it," said Talk Talk senior manager Sylvain Thevenot in a 2009 blog post detailing the problem.

The best way to find out? Turn on those holiday lights and run a speed test. Several apps including Speedtest are available to let users test their Wi-Fi speeds at home.

USA Today