Just a warning that the answer for "temperature effect on sound speed" will be totally different for air vs solids.

In air, sound speed depends strictly on temperature. This is because the bulk modulus of air is proportional to the pressure, so the sound speed is proportional to sqrt(pressure/density). By the ideal gas law, that means that sound speed is proportional to sqrt(temperature).

In solids, the effects of temperature on density and elastic moduli are not so simple as in gases. Also, in solids, there are both compressional and shear waves, vs just compressional waves in liquids/gases. Unfortunately, it's sometimes not clear from scientific writing on elastic waves in solids whether they're talking about compressional or shear waves (or both). In most cases I know of, higher temperature means lower elastic wave speeds because the effect on elastic modulus is stronger, especially for shear waves.