It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "When the call to prayer is made, Satan turns his back and flees, breaking wind audibly, so that he does not hear the adhan. When the adhan is completed, he comes back. When the iqamah is said, he turns his back and flees, and when the iqamah is completed, he comes back and puts whisperings into the heart of the one praying, saying to him: Remember such and such, remember such and such, things he had not remembered before, until the one praying remains occupied with that and does not know how much he has prayed."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2033