I've posted a few times before about problems I was having with Airplay 2, HomePod, etc. Essentially, I couldn't get Airplay 2 to sync speakers when playing from my iPhone or iPad, so I brushed it off and kept playing music to multiple speakers through iTunes as always. But then Apple upgraded iTunes to support Airplay 2 and everything just broke. Everything. None of the speakers would sync, music would crackle and cut out, the remote app would lose it's connection, and even iTunes itself would hang whenever I tried to turn on speakers. It really pissed me off, like so many things Apple these days. So I had to fix it. Here was my setup - iTunes on a Mac Mini, Velop Wifi with 3 nodes, HomePod, 4K AppleTV, and an Airport Express. My first step was to streamline my network and connect the Velop nodes via ethernet. That was just to make sure it wasn't the network causing problems. I was using two ethernet switches so I consolidated those to one. I'm not sure if this fixed anything but it was something I needed to do anyway but had put off because it required getting into the crawlspace under the house and that's not my idea of fun. Next, while I was running cables I went ahead and hardwired the Airport Express and AppleTV. This fixed the problem of iTunes freezing when I tried to switch speakers. Specifically it was the Airport Express that was causing the problem - apparently Airplay 2 didn't like talking to it wirelessly but once I hooked it up with ethernet and turned off it's radio, iTunes started responding normally. The drawback to this is that Airplay 2 won't play to multiple speakers over ethernet from a wifi device, but that wasn't working for me anyway so no loss. With that, I had Airplay working reliably with the two hardwired devices, but the HomePod was still cutting out and crackling, the synching was still off, and the remote app was still impossible to live with. I decided to check my wifi speed to see if that was the problem and sure enough I was getting a lousy 15Mbits over wifi (connected to gigabit fiber). Yikes, it checked out fine when I first set it up, so I couldn't think what had happened. I tried clearing the air a bit to see if that would help - I discovered that my cable modem still had it's wifi on even though I don't use it, so I turned that off, and I also turned off a second wifi router in my camper that I was keeping on to monitor the batteries and solar. No change. But when fiddling around with the Velop app changing channels and stuff like that I decided to turn off prioritization that I had set up for the devices I used the most, including my iPhone. Holy cow, suddenly the speeds popped up to 400Mbits! I guess prioritization isn't what you'd think. That fixed the crackling on the HomePod and the synching issues, but not the cutouts and not the remote. Airplay 2 must require some serious throughput. At that point I figured it was about as good as I'd ever get it. But I knew that the problems with the remote app had to be related to my wifi setup since it seemed to freeze whenever I moved to a different room. So it probably was caused by my phone switching to a different Velop node and perhaps the cutouts on the HomePod were caused by the same thing - my HomePod sits halfway between two nodes and will occasionally switch depending on which way the wind blows. I thought that maybe when a device switched nodes that Velop could be giving it a new IP address and that was confusing Airplay. So I went into the Velop app again and set all my devices for fixed addresses. Turns out that was it! The HomePod started playing reliably and the remote app works flawlessly. And much quicker too for some reason - there's no longer any delay with changing songs or volume. So there you go. I don't know if this info is useful to anyone else but I figured I'd post it all in case it is. I think the lesson here is that Airplay 2 requires a really cleanly set up and fast network, and isn't as robust as the old Airplay when it's thrown curveballs like IP address changes. I'll be curious to see if my network changes will make the Home app more reliable, though that's been steadily improving for me anyway via updates from Apple and Hue.