A guide vane segment for a turbomachine stage that has an inner ring segment (10) and a plurality of guide vanes (21-25) that are configured on the inner ring segment; at and/or in at least one detuning region (A; B) of the inner ring segment, that extends circumferentially in a portion of the inner ring segment that, from one end face (11; 12) of the inner ring segment to an inner guide vane (22; 24) that is circumferentially adjacent to an outermost guide vane (21; 25) adjacent to the end face and/or extends at most over an outermost third of a length (L) of the inner ring segment bounded by an end face (11; 12) of the inner ring segment, at least one cavity (112) is configured which contains at least one impulse element (100) with clearance of motion for providing impact contacts.