AC70P high frequency buzz

Product Discussion BLUETTI AC Series
1

Hi, guys
I’ve got AC70P. When enable AC power on about 40-120 watts, I get high frequency electric like buzz from my power station. Everything goes fine, no problems with power, but this buzz makes me crazy. The station is unusable in bedroom with this noise.
When the fans go faster - the buzz disappears.
Available online firmware updates are installed
Is there any newer firmware with fix?
The coolers themselves are quiet enough.

AC70P2345001277991
ARM v.2122.06
DSP v.2112.03
BMS v.2112.03

2

Hi @olegid , We currently don’t have firmware that can resolve this issue. Could you please record a video for us? Please disconnect the AC70P from any load, place it in an area away from other electronic devices, and try charging it so we can hear the buzzing sound it makes.

4

Hi, @BLUETTI_CARE
Here’s the video link

Couldn’t upload it here
My video on Google Drive

It is 75 watts on AC, 0 on DC, coolers do not spin