rem: inline double length_in_seconds(void) const { return((double)buffersize_rep / sample_rate_rep); }
add: inline double length_in_seconds(void) const { return(static_cast<double>(buffersize_rep) / sample_rate_rep); }
context:   inline double length_in_seconds(void) const { return((double)buffersize_rep / sample_rate_rep); }