Apple's new Magic Keyboard for iPad Pro has been getting rave write-ups since it was released - our review, for example, called it "undoubtedly the best keyboard you can get for the iPad Pro". But not everyone is happy.

Several users now say that the Magic Keyboard drains their iPad Pro's battery excessively, reports 9to5Mac. The problem seems most common when the iPad and keyboard are in use and the backlight is turned on, but it's even been reported in cases where the iPad is idle.

There's much in this situation that remains unclear. When it released the keyboard, Apple never said how much it would reduce the connected iPad's battery life, so it's debatable what should be considered normal performance. The Magic Keyboard doesn't have its own battery, so it's only to be expected that it will draw some power from the iPad - it's just a question of how much power drain is reasonable.

Our colleagues on Tech Advisor report that in their testing, the iPad Pro 12.9in lasted about 11 hours on its own, and 7 hours with the keyboard/case attached. That's a significant drop.

It's also unclear how common the problem is, and whether it's a fault with the hardware or software. "Perhaps the keyboard backlight is especially power-hungry in some models," 9to5Mac speculates, adding that some reports suggest the backlight may be turning on erratically.

Apple has not commented on the situation. For advice on prolonging your device's time away from the charger, read How to improve iPhone and iPad battery life.

This article originally appeared on MacWorld Sweden. Translation by David Price.