Hello Hiro - I totally agree!
I have a Grundig GDS3000 too, and since installing a TV-Link to the bedroom, I occasionally get battery warnings when using a pukka Sky remote to control the bedroom TV and the Digibox.
Yes, I use rechargeables. 2300mAh NiMHs, usually, but it depends what I've got handy and charged at the time.
But whatever I use, the battery warning is ALWAYS wrong, when it occurs.
I've even got up out of bed, wandered into the living room and pointed the self-same handset at the digibox directly, and bingo... no warning. Even from a greater distance away from the box than in the bedroom, it still doesn't show a warning. But wander back into the bedroom, and ping it at the TV-Link again from five feet, and 'bleat, bleat, battery warning' again. Load of tosh.
I wouldn't mind, if the stupid thing didn't actually PREVENT me from using the remote. I could live with the pointless warnings if I could still change the channels when it's having one of its 'moments', but no, Sky think it is more important that I get told about this flawed 'alert' to the detriment of actually being able to use my remote at all. Doh!
I'm with you, frankly, Hiro... to ENFORCE use of non-rechargeables in this way is a disgusting waste of resources, and not good, in this eco-friendly era. It is surely not beyond the wit of the pleb designing the circuit board inside the remote to COPE with voltages that are marginally lower on rechargeables. It's not rocket science, even slightly. I have a wireless mouse that bleats in a similar fashion, when used with rechargeables, and I hold that in similarly low esteem. But at least that is consistent... when it bleats about low voltages, a recharge is all that I can do... but with the Sky box, as clearly demonstrated by getting up and walking into a different room and skipping the TV-Link part of the transmission, it works fine - which just proves to me that Sky's 'detection' is flawed, somewhere along the line.
Regards