EASUN Isolar SMLII inverter chirps and charge problems

[matvox]

For some months the inverter has started making a chirp that has nothing to do with the inverter error beep. In fact, it does not give any error code.

The problem occurs when there is good production from the panels and low load, i.e. a high battery charge current. The charge current limit is set to 60A. When I exceed a certain amperage it starts to "chirp" and the charge power goes from 2.5kw to 1.9kw suddenly, and then it tries to go back to 2.5 and suddenly falls below 2 (see video).

I set the maximum charge current to 20A, and it doesn't seem to cause the problem anymore, even if a slight background croaking is heard, if I put 30A the problem comes back, the power rises and then drops suddenly with the usual background chirping.

What electronic component can make such a whistle?

Video:

Data
EASUN Isolar SMLII 5.5KW inverter
10 Jinko panels 340Wp = 3400Wp
16 cell EVE LF280K battery
5A active equalizer
JBD 150A passive equalizer

 

[Mattb4]

The chirp must be out of my hearing range. All I hear is the fan noise. The sudden wattage change could be due to charging parameters. If the battery goes from bulk to float you will see a large drop off in solar panel wattage. As battery voltage rises and falls the amount watts the SCC delivers changes quickly.

 

[matvox]

The chirp must be out of my hearing range. All I hear is the fan noise. The sudden wattage change could be due to charging parameters. If the battery goes from bulk to float you will see a large drop off in solar panel wattage. As battery voltage rises and falls the amount watts the SCC delivers changes quickly.

here you can listen the chirp better
https://drive.google.com/file/d/1yOsUNlYsBj-IjesE_264DG1TwHGM8jDt/view?usp=sharing