I investigated a bit deeper this aspect of LinkPlay-based devices (have 3 of them). Using recent firmware versions, higher than v4.2:
- that almost every 2 second connection is NOT chinese IP addresses, but to
media-router-fp1.prod1.media.vip.ir2.yahoo.comormedia-router-fp2.prod1.media.vip.ir2.yahoo.com, these seem to be required by Spotify Connect functionality (when your speakers appear in the Spotify app and you can play music straight from the speakers and the app is just a remote, needs Premium account). When I blocked access to these, everything remained functional EXCEPT Spotify Connect (speakers disappeared from the Spotify app). - more rarely, but still repeatedly there are connections to
*.bc.googleusercontent.com- these seem to be related to Spotify playback. When I blocked access to these, Spotify music playback stopped after some seconds (buffer got empty, unable to download next bit of music), and I was unable to start another track to play - more rarely, but still repeatedly there are connections to various IP addresses belonging to Amazon, some of them I was able to reverse lookup as being related to Amazon Alexa. Since I am not using Alexa at all, I was not able to confirm what functionality ceases after I blocked them.
- after booting, the device connects to
121.41.90.151which is indeed a chinese address, but after some investigation I found that the device is looking for firmware updates at that address. This happens more rarely, I only caught it once during my packet sniffs after a reboot.
I don’t think the Linkplay module does anything worse than Sonos does. There you can’t even use the speakers unless you forcefully accept to share data.
I also tested my linkplay devices completely offline from the Internet for a few weeks (put them in a separate network where there’s no Internet access at all, I only made exceptions in the router’s firewall for the couple of webradio http streams and nothing else). They continued to work perfectly. Played my local music, played those webstreams I allowed only, played TTS and local sound alerts from HA and all worked well. Multiroom also. Using this HA integration with Linkplay. Of course with no internet access I lost Spotify Connect functionality which requires a paid accoount anyway. The Android app controlling the speakers displays a message that the speaker has no internet access - so you can’t select online services from there but that’s exactly what I wanted during the test.
If there are privacy concerns, the best approach is to keep sensitive devices offline from the Internet. Linkplay-based devices can be kept offline and be still functional with Home Assistant in the same time IMHO. No need to forcefully accept various privacy policies you can’t even understand etc…