YouTube has made some changes to its recently introduced commenting system admitting that has caused increased spam on the site. Earlier this month the Google-owned site overhauled its commenting system to push better quality comments and ones from certain people higher up, while diminishing less important or spammy posts. As part of those changes, users were also forced to sign up for Google+ and comment using that account.

However, Youtube said that the new system didn't work as it was expected, and it introduced new opportunities for abuse.

To reduce the spam, YouTube has made a number of updates to the site, the company said. The fixes include better recognition of bad links and impersonation attempts, and changing how long comments are displayed, YouTube said. The site is also improving its detection of ASCII art, the graphic design technique known for producing in-comment images made from text characters.

New features like threaded conversations and formatted comments will continue to improve the site's comments, YouTube said.