audacity doesn't record stereo on my pc

i’m usin audacity (2.0.3) to record some old tapes on the pc but on my pc (TOSHIBA satellite C850-1C0), even if i’m recordin stereo and the source is stereo the left and right channel are exactly the same, in fact i record two mono tracks, instead of a left and right channel. I tried it on two more pcs and on one (don’t remember the model) it had the same problem while on a dell 15rSE everything was fine, i got a perfect stereo recording. How can i try solving that problem? what could be the source of that problem?
thanks for the help

How are you doing that? An Ion USB cassette player? An old Revox reel to reel tape machine plugged into the laptop microphone socket? Other?

i tried both an usb analog audio reciever and an analog stereo to 3.5mm cable, both work with the dell, not with toshiba…

Check in the recording setting in the vWindows Sound Control Panel that the device is not set to record mono.