In some embodiments, a method includes detecting a tone in each data frame
of a sequence of telephony signal data frames. A first data frame of the
sequence of telephony signal data frames may be transmitted immediately
after detecting the tone therein. Transmission of a last one or last ones
of the sequence of telephony signal data frames may be deferred. It may
then be determined whether the tone is present in a next data frame that
immediately follows the sequence of telephony signal data frames. If it
is determined that the tone is not present in the next data frame, the
last one or ones of the sequence of data frames and the next data frame
may be transmitted. If it is determined that the tone is present in the
next data frame, a respective replacement data frame may be transmitted
in place of each one of the last one or last ones of the sequence of data
frames and in place of the next data frame.