For example, if the following was still enabled (it is by default) then all bets are off for WiFi getting all possible access to the air.
Read https://www.howtogeek.com/224981/how-to-stop-windows-10-from-uploading-updates-to-other-pcs-over-the-internet/
Another issue is that WiFi gets clogged up fast if other users are watch Netflix, Youtube and such.
-> What is this about a new machine having WiFi issues? HP is not known for making bug free machines.
Finally 8 devices is a stretch. I doubt anyone has this setup or will tell us it's OK.
I have been using Airplay with iTunes for years and have added AirPlay speakers (7 Logitech UE Air speakers and a new Yamaha RX-A770 receiver). One or more speakers and/or receiver drop out, reconnect and drop out and sometimes come back on to work fine, sometimes come back out of sync with other speakers. Cell phone usage causes problems too. Thinking other programs are hogging WiFi, I wiped my Sony Vaio laptop (seventh gen i7, 8 GB RAM, 1 TB SSD) and installed Win10 Pro, iTunes and NOTHING else. To eliminate one leg of the WiFi process, I ran ethernet from the laptop to the router, which is a new Lynksys EA9300 (a Max-Stream AC4000). We still have the dropouts and sync problems. A new 8th gen i7 HP laptop has the same issues using a WiFi connection. Space contraints prohibit discussing everything I have done to try to fix these problems.
Most of the time, AirPlay works fine with all 8 airplay devices, but it's a pain in the patootie other times. Anybody have a fix?

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