Musnad Ahmad

It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: When the call to prayer (adhan) is given, Satan runs away while passing wind loudly so that he does not hear the adhan. When the adhan is finished, he comes back. Then when the iqamah is started, he runs away again, and when the iqamah is completed, he comes back again and puts whispers into the heart of a person and says, "Remember such and such thing, remember such and such thing," and he reminds him of things which he did not remember before, to the extent that a person does not even remember how many rak‘ahs he has prayed. When this happens to someone, he should perform two prostrations of forgetfulness while sitting.