Mysolarpv - wrong totals in "history"?

I noticed something strange: the totals for use/solar/direct/export/grid are incorrect in “history”.
When i click the bar (and the 24h graph is shown), the correct values appear.
The difference for march (27 days) is approx. 11% lower (848 kWh vs the correct 1094kWh for “grid”)
Any idea’s where it’s going wrong?