Having adjusted the sync values a few times I have not got to a point where my batteries and BMV show the correct SOC. This is especially a problem in winter. Now the specific gravity is showing around 60% and the BMV thinks it has around 90% SOC. How can I adjust the BMV. On my previous system [non Victron] the unit allowed easy manual adjusting of the SOC so it was a simple process of checking regularly and updating the system.