YouTube has begun taking strict measures against users of ad-blocking tools, as some users have reported abnormal behavior while browsing YouTube with ad-blocking tools, noticing that videos are being skipped to their end or muted automatically.

According to Independent’s publication, a user shared their experience on Reddit saying: “When using an ad-blocking tool on YouTube, the sound stops after a few seconds. I can raise the volume bar, but it gets muted again immediately.” Another user added: “When I play a video with ad-blocking, the sound starts for a few seconds then goes silent. The video plays normally, but without sound. I thought there was an issue with my headphones or computer.”

Ad-blocking tools like browser add-ons are widely used to filter out the browsing experience from annoying online ads.

YouTube had previously announced that it would start taking action against external applications that block ads, confirming that they violate the terms of service.