While Apple’s recently released HomePod speaker has managed to impress most audiophiles, it’s also leaving the wrong kind of impression with owners of wood furniture who are discovering an unfortunate mark on their tables.

Reports of the $350 smart home speaker leaving marks on wood finishes began surfacing on social media and as experts got their hands on the device to review it. At issue appears to be a silicone base that leaves marks when interacting with certain oils used to finish wood furniture.

Product reviews published by the Wirecutter, as well as Pocket-Lint, first raised the issue in their reviews of the Apple HomePod. Wirecutter noted, “An unhappy discovery after we placed a HomePod on an oiled butcher-block countertop and later on a wooden side table was that it left a defined white ring in the surface.”

Pocket-Lint offered a similar observation in its review, stating, “Within 20 minutes the HomePod had caused a white discolored ring to appear on the wood that some days later has faded, although still hasn't completely disappeared.”

The publication went on to say that the HomePod was tested on a number of other surfaces—including wood surfaces that hadn’t been treated with oils—and found there were no markings produced in those cases.

Still, it’s far from ideal for the HomePod to literally leave its mark on the table or entertainment center that a person decides to place it on. Apple provided no warning at launch about the potential marks, but consumers found out the hard way when they set up the speaker and started playing music.

Early adopters of Apple’s speaker—designed to compete with Amazon’s line of Alexa-powered speakers and Google’s family of Home speakers. “[HomePod] left rings on my wood furniture in less than 20 minutes of use,” one user on Twitter wrote . “Thanks [Apple] I am glad a paid $400 to make perfect etched circles on my more expensive furniture.”

At issue with the HomePod is not so much the fact that it leaves rings on certain furniture (though it’s far from ideal) and more the fact that Apple didn’t bother to provide consumers with a head’s up regarding the issue, which can easily be mitigated by placing the speaker on a safe surface or setting a coaster or cloth under the speaker before setting it on wood furniture.

Apple has since acknowledged the issue and updated its support page for the HomePod with additional details about the smart speaker and how its silicone base interacts with certain surfaces.

Found under a heading titled, “Where to place HomePod,” Apple explains:

It is not unusual for any speaker with a vibration-dampening silicone base to leave mild marks when placed on some wooden surfaces. The marks can be caused by oils diffusing between the silicone base and the table surface, and will often go away after several days when the speaker is removed from the wooden surface. If not, wiping the surface gently with a soft damp or dry cloth may remove the marks. If marks persist, clean the surface with the furniture manufacturer's recommended cleaning process. If you’re concerned about this, we recommend placing your HomePod on a different surface.