Battery offset

Hi,
I have a Devo 10 with a pretty new nightly (deviation-devo10-v5.0.0-db496d9) with a 2S LiFePo4 battery. The problem is the batteries voltage is 6.66 Volt measured with a multimeter. But the tx shows me 6.47 V. Is there any way to set an offset or do I just have to set my battery warnings lower?

Thanks in advance
Mario

I think it is fixed, but this issue is known been discussed before.
Would be nice to have offset and scalefactor in hardware.ini.