https://www.techradar.com/news/apple-admits-your-homepod-might-stain-wooden-surfaces

Apple has acknowledged a number of complaints from users who say their HomePod speakers are leaving white rings on wooden surfaces, admitting that "it is not unusual for any speaker with a vibration-dampening silicone base to leave mild marks when placed on some wooden surfaces".

Numerous reviews and users on Twitter have been pointing out the major flaw in Apple's new smart speaker, which is apparently caused by oils diffusing between the silicone base and the surface of the Apple. The marks should be able to be cleaned off and will fade gradually anyway, the brand says.