Apple’s HomePod is a great-sounding but ideologically flawed speaker, and it turns out there’s another major problem with the smart speaker aside from its lack of support for Spotify. Apparently the silicone base of the HomePod can damage wooden furniture, with multiple outlets (including Wirecutter and Pocket Lint) reporting that leaving the speaker on top of wooden surfaces can cause a white ring to form.

Apple has confirmed the issue to Wirecutter, stating that “the marks can improve over several days after the speaker is removed from the wood surface,” with the company also recommending that users “try cleaning the surface with the manufacturer’s suggested oiling method” if the white rings don’t fade. Given that HomePods aren’t meant to be put on a soft surface (the tweeters fire down, so putting it on cloth messes with the reflectivity of the sound), it’s not the sort of problem you can solve by just putting down a cloth underneath it, either.

Congratulations to everyone on their beautiful HomePods and sorry it secretes a deadly acid that destroys your furniture https://t.co/p1eSAvjCbW pic.twitter.com/uVhAFbIlRJ — Casey Newton (@CaseyNewton) February 14, 2018

Apple has also updated its official support page for the HomePod, explaining, “It is not unusual for any speaker with a vibration-dampening silicone base to leave mild marks when placed on some wooden surfaces.” According to the support page, the marks are apparently caused by “oils diffusing between the silicone base and the table surface.” In addition to the previously stated advice about hoping the marks go away or cleaning the surface, Apple also said for customers who are concerned about the issue, “We recommend placing your HomePod on a different surface.”

Update February 14th, 4PM ET: Added additional information about placing the HomePod on soft surfaces. Updated post to reflect new information from Apple’s official support page for the HomePod.