does a wireless keyboard/ mouse

[Mal X]

have to be in direct line of fire to receive a signal......i.e i sit in a sofa gaming and my knees block the line of sight to my pc, which is lower down on the floor

 

[jak731]

depends on the wireless mouse and keyboard in question

 

[Werewolf]

Generally with modern ones direct line of sight isn't required (fortunately we got past the days of IR units a while back ), exactly how good they are at dealing with obstacles and the range varies a lot depending on the model/battery level.

 

[Audigex]

For the vast majority no, most are either bluetooth or some other form of radio-style wave - rather than Infrared which requires line-of-sight.

Just make sure you don't get an Infra Red/Infrared/IR set and you should be fine. There aren't many which use IR

 

[Mal X]

ok thanks, i think i had infra red before...it was cutting out all the time