const { dBFS, floatTimeDomainData } = await getChannelMaxRMSdB(idOrSrc, duration);
// The floatTimeDomainData is an array of the waveform data used to calculate the dBFS values.
const { dBFS } = await getTrackMaxRMSdB(duration);
const totalDBFS = combineDecibelLevels(dBFS):