I’ve got a Raspi 1 and exactly the same problems. Newest version of Volumio booting up without problems, then I configure it, register my >50k titles lan-library and let it index it. Lasts a long long time, approx. 10 hours or more. Afterwards, if I ever reboot the device, it won’t come up again, hangs at some obscure point, won’t be reachable neither via webgui nor via ssh, “connection refused”. It’s registered correctly in my LAN, the router displays the correct IP. Only thing that helps at this moment is to reflash the card.
Did this several times, nothing changed, so I reverted to 2.586 as suggested here, and it’s back to normal! Working flawlessly. Indexes the whole library in less than an hour, no problems with rebooting, menus much faster etc.
Conclusion: Versions after 2.586 are incompatible with Raspi 1. Don’t update.