Battery Backup Buzzing

[dmw16]

My 6 month old APC battery backup is buzzing pretty loudly. Is this something I should be worried about? Will APC fix this?

 

[MustISO]

Which model do you have? I have the Back UPS XP 900 and it always sounds like the fan is running in it. If it even has a fan. When the power goes out it makes a loud buzzing noise. I wasn't sure if this was normal or not.

 

[dmw16]

No big fan. I think it is a 1500AV. It only started recently. Not sure what to make of it.

 

[mrSHEiK124]

I've got one of the narrow/tall 1500VA units (from Sam's), and it always buzzes if it's on battery power.