Yes, I just got a new EB3A unit today (Aug 19, 2023) and the fan makes a significant buzzing sound when the fan starts up for about 30 seconds until the fan spins up to full speed.
The biggest problem with this is for anyone who works around servers or other electronic equipment it sounds like a device with a fan that is blocked or going bad, it’s a real problem if you have it in UPS mode because any time the fan spins up in your equipment closet (in my case just a closet with my home network gear) it sounds like something is broken. Fan noise is fine, broken sounding buzz not so much.
My guess based on the behavior is there’s a current ramp to the fan that isn’t quite high enough to start it spinning cleanly without the long buzz. It needs an initial higher current to start it cleanly (startup noise should be short if at all) then the current to the fan can drop to keep it spinning.
Not sure if this is something that could be addressed in firmware?
I also received a brand new EB3A unit this week (Aug 27, 2023) and first time charging the buzzing started,
it also buzzes annoying loud when nothing is plugged in and is sitting at 100% charge.
I purchased this unit (like many people I presume) for camping but this annoying buzzing/vibrating is unacceptable
I contacted customer support with a video showing the buzzing and they responded claiming tech support said this was normal!
Wait what? Seriously?
The company is ok with releasing a product they know has a design flaw and I guess shrug it off as no biggie!
Looks like this thread is over a year old so not holding out for any firmware update
- the only input from Bluetti Admin here in this thread was to suggest putting in ‘Mute mode’?
Obviously they meant Silent mode but yeah that doesn’t work either as its buzzing when nothing is plugged in.
I agree. The buzzing is caused by the fan power circuit on the board and not the fan itself. I experienced the same thing with one of the first EB3as out and have seen no movement towards fixing the issue or acknowledging there is one.