Crash with echo cancellation enabled

[samuelv@xxxxxxxxxxx (Samuel Vinson)]

Hello

When I enable echo cancellation, my app crashes on iphone

Thu Mar 12 21:27:09  Assertion failed: (N>0), function 
echo_supp_cancel_echo, file ../src/pjmedia/echo_suppress.c, line 678.
Here is the lines of code :
    N = ec->samples_per_frame / ec->samples_per_segment;
    pj_assert(N>0);

Do you have an idea where is the problem ? Do you have an idea how to 
resolve this issue ?

Thanks in advance.

Samuel