I noticed that this bug happens quite frequently when my ping spikes or I experience some packetloss. Also probably related bug, often when you spawn your accuracy gets stuck on "running" mode, e.g. the crosshair is huge and doesn't tighten up even when you crouch. Again, jumping once fixes it.
Had that a lot too. I've found that you have to fall off something (even as small as a kerb) to return it to normal =/
yeh and usually it takes an extra second after ducking to get it to work Really miss how we could jump and shoot the mortar ;D