I’m a long time user of the Logitech Squeezebox family and with the Home Assistant integration my players are well integrated.
However hardware fails and getting players becomes increasingly difficult.
I recently found out about volumio. Am I right to understand that by running volumio on a say Raspbery Pi coupled with an external DAC I could replace a Squeezebox player? If so what DACs do people use to get some decent (while not audiophile) sound? There is an integration for Home Assistant so would fit nicely into my environment.
I’ve never used a Squeezebox player, so probably not the most informed to answer your questions.
Yes, but whether it would fulfil your expectations is another thing. You don’t say what these are. There are a couple of plugins in Volumio that would be of particular interest to you (Volumio Plugins Collection): the LMS and Squeezelite plugins.
There are loads of DACS to choose from and if you’re looking for excellent sound at a good price, then i2s DACs are hard to beat. Of course, you can always attach a standard USB DAC.
The big problem you will have in moving to Volumio will be the lack of support for Home Assistant. Both Google’s & Amazon’s automation options are scarce in Volumio; I’m not sure why, but suspect it is a matter of user priorities for their audio experience.
Edit re. Alexa/Home Assistant: also you don’t have the fine control, nor search etc.
I were used Squeezebox Touch for many years, and I loved it, but Squeezebox hardware get old, so I’ve tried two years ago Volumio, and I don’t miss Squeezebox, Volumio works much faster, I can play DSD files without any problems. I’m using Volumio with Raspberry Pi 4 (4GB Ram) and official 7’’ touchscreen, so it looks like bigger Squeezebox Touch. I also use FLIRC Ir dongle, thanks to this I can control volumio with universal remote (Play, pause, next song, previous song). I’m keeping my music library on Synology NAS drive. Volumio is connected to Audiolab M-DAC mini, and i really like how it sounds. If you want cheaper DAC, I can recommend HiFiBerry DAC+ Pro RCA, which I also have for my second Raspberry Pi, and for it’s price sound really well. Sorry for my terrible English 
Thanks for getting back. You’re right that the hardware gets old and even though they are nicely designed players - especially the Classic - it’s time to move on.
Maybe I try to install Volumio with the Spotify plugin (I have a premium subscription for a while) on a Pi 4 I have at hand and use the HDMI out to my A/V receiver more from the perspective of overall experience; e.g. usability, navigation. I know that I can always upgrade by adding a DAC (USB or otherwise) if this works well.
The integration with Home Assistant allows me to control the player (start, stop, volume, track +/-). I can also access music and plugins (e.g. Spotify), web radio etc. There doesn’t seem to be a search function but it’s early days in looking through the documentation.