Echo Cancellation Problem (MATLAB)

>
> The audio was recorded from the speaker and mic channels of a PC sound
> card. The DAC sampling rate is slightly different from the ADC sampling
> rate. The gradual sliding of the signals with respect to each other means
> the canceler never converges.
>
> Not all sound cards do this, but it is very common. The ADC is locked to
> the SP/DIF input, which is slaved to whatever drives the SP/DIF input. If
> there is no SP/DIF signal the ADC rate free runs. There may or may not
> actually be a SP/DIF connector on the machine. The DAC rate, meanwhile,
> comes from a local crystal. The two rates are not locked, though they
> remain fairly close to each other. This is hugely annoying for a lot of PC
> audio applications, but that's just how it is and you have to live with
> it.
>


Is this something I can verify somehow by analyzing the actual
signals???
If so, how?