To clarify for the many replies since Matthijs’ post;
Since firmware release v3.61, the behaviour of the chargers with this hardware fault will be more apparent.
The difference in behaviour appears when the battery is not fully charged and the charger will keep toggling every few seconds between bulk and absorption. This is also visible on the charger itself as the LED indication the switches between Bulk and Absorption.
This change in behaviour is not the cause of the fault, nor is it a result of the firmware update.
A charger that is showing this characteristic still had this fault in its hardware before the firmware update, and downgrading the firmware will not remove the hardware fault.
It just was not apparent on the LEDs. Degraded charging performance is the same in both cases.
So the advice remains the same as in Matthijs’ post from December, if this behaviour is seen the charger is faulty and needs to be replaced under warranty.