Took a quick look at this and I was able to reproduce, unfortunately only occasionally. Most of the time it worked OK. That’s harder to find than a solid failure, so I’ll have to stick in some diagnostics to get to the bottom of it. Not a high priority right now.
It would be helpful if you could determine if its solid for you, cite the version of firmware you are using, and post the problem under issues on Github. IotaWatt will be getting more exposure in the months to come and I need to start using the github problem management system to keep track of everything and manage multiple incidences of the same problem.
Thanks