Another digital tacho question

It needs to go back to main dealer to be recalibrated to go to other work

Kenny1975:
Was driving a brand new MAN TGA 440 with Siemens Digital tachograph, went in shoved in digi card, modded entry, went away did my checks. Finished my checks was told wouldnt be leaving for an hour so put it on POA, went away locked up cab to have a coffee and a chat.

Come back an hour later find tachograph on rest, think well musta put it on rest by mistake. Go out start doing my run, go to a place other work for 1hr unloading truck check before i leave cab its on other work, back in cab tacho an hour later it has been on rest for an hour.

Turns out with this siemens everytime you remove the key the tachograph will go onto rest and start flashing for about 10secs giving you the option to change it to another mode.

Is this a fault or new way they are setting them up. Its a pain in the arse because if you stop automatically goes to other work as usual, but as soon as the key is removed it goes onto rest, which is a pain because as soon as you remove the key the tachograph is no longer illuminated and you can’t see it.

Spoke with TM about it thought it was strange knew nothing about it tho.