An audio codec in a wireless device may be utilized for up sampling two or
more audio signals to a same data sampling rate. Each audio signal, such
as digital audio, voice, and polyringer, for example, may be received at
one of a plurality of data sampling rates. Audio signals may be equalized
and/or compensated with an FIR filter before up sampling or with an IIR
filter to reduce overall processing latency. Multiple half-band
interpolation operations may perform the up sampling. The first half-band
filter may be replaced by an IIR filter to reduce overall processing
latency. A gain of the up-sampled data may be adjusted to reduce noise
effects. The channels of the up-sampled audio signals may be mixed and
later further up sampled for subsequent communication to an output
device. The up-sampled mixed audio signals may be down sampled for
communication to a Bluetooth radio.