The high‐frequency precessional mode of a hot‐electron‐stabilized magnetic configuration has previously been shown to be stable in a window of core‐plasma mass. Under conditions of frequency matching, the resulting stable negative‐energy precessional wave can be destabilized by coupling to positive‐energy shear‐Alfve´n waves. Coupling is avoided when the hot‐electron precession frequency exceeds the core‐plasma ion gyrofrequency.