Muse Proto + Squeezelite: Losing WIFI connection

I’m using four Muse Proto units with Squeezelite for my multi room setup (firmware I2S-4MFlash-1334). Recently they started to randomly drop from the WIFI and enter access point mode (maybe a new neighbor with a lot of network “pollution”). So I enter my WIFI credentials again and at some point they drop again. This is very frustrating and I’m wondering how to solve this. I couldn’t find anything to let Muse Proto units keep/remember the credentials. I really don’t want to move back to ESPHome for the speakers and lose my synced multi room sound (with ESPHome the credentials can be baked into the firmware). So far I was only able to install Squeezelite with the web flash tool. Does anyone have a solution/workaround for this?