Occasional Crashes with Raspi 3B+, Allo Boss Setup

Hi Volumio community

a few weeks ago a set up my first Volumio installation. Most things worked as advertised and I really like what I see. Much to my regret I’m experiencing occasional crashes, which is holding me back from finally retiring my Chromecast Audio. Maybe, hopefully someone in the community can point me in the right direction, so I can dig deeper.

Volumio Information

Volumio Version: 2.861
Hardware: Raspberry Pi 3 Model B Plus Rev 1.3 connected via Wifi
DAC: Allo Boss
Plugins: Spotify, Spotify Connect

What did I try so far? Not much really - just scanning the output of

journalctl -p 7

The only thing which irregularly (1 to 3 times a day) occurs is a loss of wifi with a message like

dhcpcd[1036]: wlan0: carrier lost

and subsequent system reactions. Sadly I have never been able to capture the log messages leading up to a crash, as everything is kept in memory. Setting Storage=persistent in journald.conf did not help, other than reducing the number of log messages.

Now my questions are twofold:
Is there an easy way to keep the logs over a crash by persisting it on the sd-card?
Or are there any other hints on where to look further for the reason of the observed instabilities?

Any help is much appreciated!
Matthias