Speex dev - Jun 2010 - accessing AEC delay estimate?

Hello -

I'm working on improving the robustness of AEC on Android phones.
With the audio API I'm given, there's no way to detect a microphone
buffer overrun.  While overruns don't happen often, they are possible,
and I'd like to handle them gracefully.  Currently, repeated
microphone overruns cause the offset between the capture and play
samples to increase over time, unless eventually they are too large
for the AEC to handle.  If I could use the current delay estimate from
Speex to detect when this was starting to happen, I could correct for
it automatically.

Is there a stable delay estimate I can watch to detect this condition?
 Or perhaps a way this could be determined given the information
provided by SPEEX_ECHO_GET_IMPULSE_RESPONSE?

Thanks,

Stuart Anderson