We've been seeing this problem recently too (after never seeing it for years.)  I'm not expert but I'm thinking that since this problem began to affect people without Meraki's firmware changing, I think the common culprit might be something like the Chrome (and/or Safari) browser.   I believe the Chromecast uses mDNS/Bonjour so is it possible that when a user launches Chrome, the browser uses mDNS to search for any available Chromecast devices (to display on the cast tab) and Meraki is picking up the mDNS name linking it to the PC for the dashboard description?  Obviously, if this theory is correct, we all started seeing the problem after Google updated Chrome to some specific version...   Right or wrong, I agree that Meraki should allow us some control over the prioritization of protocols so we can have it ignore the mDNS transmissions and keep our dashboard clean and manageable! ... View more