UPDATED May 5:
I apologize to the forum for mixing two different problems. They are unrelated.
Problem #1: User error. I thought I was using a class 6 SD card but I was wrong. The yellow "!" indicates a pathologically slow card. Upgrading to a class 10 resolved this problem.
Problem #2: UNRESOLVED. Red battery indicator comes on prematurely. On a fresh charge, it'll turn red after recording for a couple of minutes. On a partially drained battery, it turns red immediately upon entering movie mode or pressing the record button. Turn the camera off and then right back on in "still" mode and it shows full charge and works fine ... until trying to shoot video. I have not precisely measured recording times but it'll record for at least 20 (maybe 30?) minutes while flashing red.
I can't return to Amazon OR Canon for full refund??? I'm just going to try the fuzzy velcro and see what happens. I did discover the battery life is extended using CANON BRAND batteries vs generic batteries so that helps some.
Today my new SX280 arrived and I have the battery problem too.
A fully charged battery can only take max. 12 min. video and 30 photos taken in a total time off 20 min., with turned off GPS and Wifi. During this 12 min. video-session the camera has 3 times shutting itself down due low battery, at least that what it says.
I have the battery temperature measured with specialized tools when I noticed that it was warming up during video.
The battery temp. Is rising above the 30 Celsius shortly after filming as the outside temp was 21 Celsius.
The voltage was dropped to 3,77V (full charge is 4.2V).
Some might think that 3,77V should still be enough because it is a 3.7V battery, but its not for an unconnected battery.
Unconnected the voltage is always higher than when the battery is delivering current. When its delivering current its not healthy for the battery when it is dropping below the designed voltage (3.7V).
The cause that the indicator gives 3 digits and fully charged when after shutdown and startup again is normal for li-on battery. The battery needs some short time to recover to give full voltage again but after new startup the video I can take is after each startup is much less. The indicator on any battery powered device is mostly not reliable because it is measured true voltage and the voltage can fluctuate. If no current is asked then the voltage id going up and with more current the voltage is dropping. So this is why the indicator on the SX280 gives on time full and the other empty but when the camera is shutting down it is really empty.
I think the problem can not be resolved with an update of firmware, because the SX280 consumes tot much current for this battery. If it was only an indicator problem the camera would not shutting it self down and more important the battery would not heating up, which is an indication of delivering more current than it is designed for.
The side affect of this is not only that someone runs out of power but the battery life too is shortened due to the heating up.
I hope to hear soon from canon else I must returning this nice and good camera because an empty battery is very annoying.
It will be a while- I shipped my camera back to Canon with their free ground UPS shipping from NY- Thursday night 5/23- because of the Holiday it is not due to arrive to Irvine CA until Friday 5/31. THEN 5-7 workdays before it is returned to me....it will be a while.