[Observium] Accurate Graphs in Billing are probably not so accurate

Hi

I've noticed two things in the "Accurate" graphs in the Billing part:

1. Are Interface counter overflows or equipment reboot) probably not catched? - I see very high spikes (200 Gbps and more) on a 1G interface sometimes in sometimes out, but not at the same time. the quick graphs are ok

2. If I monitore more tha one interface for billing (Unfotunately one of the is down) the accurate graps are at leaset 1000 times to high...

Atached some graphs...

I runn lates svn (0.12.9.3378).

Any ideas ?

Regards

Matthias