Bug when quickly alternating between dragging a box to select units and hitting a control-group hotkey

This is a little hard to explain, but if I create a control group hotkey (let’s say of just my TC at the start of a game), and then rapidly alternate between dragging a box to select units (e.g., villagers under TC) and hitting the control group button to select the TC, then after a few alternations it will basically “lock” the control group key for a few moments, not allowing selection of the control group for a second or so despite pressing the control group button.

Hope that makes sense. Thanks!