In this paper melting and crystallization of the indium-gallium alloy with indium content of 4 at. % embedded into the porous glass with pore size of 7 nm were studied using acoustic methods. Temperature dependencies of the velocity and attenuation of the ultrasound were measured in a wide temperature range. The expansion of the temperature range of the melting of α-Ga was observed. An anomaly on the temperature dependences of the ultrasound velocity and attenuation near ~223 K was revealed which is probably related with the formation of a small fraction of β-Ga.