325i Voltage level isssue

[DoneRightBimmer]

My 325i is having a voltage issue. New battery and bosch Alternator.
Voltage level with engine off is 12v when at idle with no accessories i get 13.8v but at idle with headlights fogs and heater i get 12.0-12.3v. When driving I get 13.6-13.8v regardless of whats on. Any ideas of the what could cause the drop could it be voltage regulator, even though its new and only has about 5000 miles on it.

[spdracrm3]

perfectly normal ,you'll find if you rev engine with it fully loaded voltage will rise ,its just that at idle the alt isn't spinning fast enough to reach voltage cutoff point . as long as voltage doesn't drop below 12v at idle and never goes over 14.5 everything is normal.