Hi @Ed van den Enden, I think your BananaPi runs an Allwinner SoC, which is similar to the OrangePi zero. Can you list the RTCs on your board? ls /dev/rtc* On my OrangePi's here, the H2+ SoC also has an RTC that is wildly unprecise, but it's still used as /dev/rtc0 and therefore used by the kernel to synchronize to when the kernel boots.   I do not know much about your SBC, but perhaps sharing my config for the OrangePi zero helps you as well:   I have two RTCs, on