You’ll need to downsample them to 48kHz to play on Sonos. A simple batch processing exercise if you choose the right software.

wich software you suggest?

I’ve always used dBpoweramp Music Converter. It’s often recommended, but isn’t free. That said, there is a trial period.

wich level you choose normally? 

Do you mean the FLAC compression level? I usually just leave such things on the default setting. It doesn’t change the quality -- it’s lossless -- only the final file size and the encoder CPU effort required.

where i change the cpu effort? on advanced settings?

because i made the audio conversion and the final file i cannot play it on sonos speaker, i have the same information about the flac audio file

is the resample frequency? from 24000 to 16000?

Standard CD is 44.1.

yes, 44100, then the file size went from 100mb to 30mb

You don’t want to resample 192kHz to 44.1kHz. The maths is awkward. Use 48kHz instead. It’s an exact quarter of the original sampling rate, so the decimation is simple. 

ok, thank you. like this

Correct.