Since two weeks my UPS shows on display on 2-4 dots for battery capacity. PowerChuze shows that it‘s at loading all the time.
I also replaced the battery with a new one and did a selftest that passed.
My UPS seems broken so I bought a new one (Back-UPS Pro 550). This one has a strange coil whine / hum. Every 3-5 seconds it hums for about 1-2 seconds even if battery is full.
I think it's time to change the manufactor.
Sorry for the inconvenience. If you feel the new UPS is not working properly you should contact local support. They will assist you and if needed provide a replacement.
Here is a link to APC.com where you will find contact information for local support.
Choose a location