In a gas turbine having a device for the fuel injection, which injects fuel into a mixing device (12), the injected fuel being mixed with combustion air in the mixing device (12), and in which the gas turbine also has a combustion chamber (16) arranged downstream of the mixing device (12), the length of the combustion chamber being LBK and the length of the mixing device being LMix, in order to suppress thermoacoustic vibrations the premix combustion chamber (10) containing the combustion chamber (16) and the mixing device (12) is designed in such a way that an acoustic pressure fluctuation which occurs in the premix combustion chamber (10) at the combustion-chamber outlet (20) is superimposed in phase opposition on an entropy-wave-induced pressure fluctuation at a certain frequency to be damped.