Shift click to place hoppers doesn't work

i'm using pc win 10, v 1.1.5. im trying to place hoppers like i used to using shift (sneak) and click (NUM2) but it doesnt do anything.

Sneak (shift) works fine to sneak/crouch on its own.

i can place hoppers fine if i click onto the side of a block - thats the only way i can get hoppers to link up now. However this doesn't work if i want to build a hopper clock (two hoppers linking each other).

Shift click doesnt just affect hoppers either, if i hold down shift it wont place anything.

Control button is my sprint key and that just opens the hopper inventory.

please can this be looked into ?