My uncle asked Messenger of Allah ﷺ about a person who imagined to have passed wind during the prayer. Allah' Apostle replied: "He should not leave his prayers unless he hears sound or smells something."  

أَنَّهُ شَكَا إِلَى رَسُولِ اللَّهِ ﷺ الرَّجُلُ الَّذِي يُخَيَّلُ إِلَيْهِ أَنَّهُ يَجِدُ الشَّىْءَ فِي الصَّلاَةِ فَقَالَ لاَ يَنْفَتِلْ أَوْ لاَ يَنْصَرِفْ حَتَّى يَسْمَعَ صَوْتًا أَوْ يَجِدَ رِيحًا  

"A man who felt something during Salah complained to the Prophet ﷺ. He said: 'Do not stop praying unless you notice a smell or hear a sound.'"  

شُكِيَ إِلَى النَّبِيِّ ﷺ الرَّجُلُ يَجِدُ الشَّىْءَ فِي الصَّلاَةِ قَالَ لاَ يَنْصَرِفْ حَتَّى يَجِدَ رِيحًا أَوْ يَسْمَعَ صَوْتًا  

"A complaint was made to the Prophet about a man who sensed something (some doubt about his ablution) during prayer. He said: 'No (he does not have to perform ablution) unless he notices a smell or hears a sound.'"  

شُكِيَ إِلَى النَّبِيِّ ﷺ الرَّجُلُ يَجِدُ الشَّىْءَ فِي الصَّلاَةِ فَقَالَ لاَ حَتَّى يَجِدَ رِيحًا أَوْ يَسْمَعَ صَوْتًا  

[Machine] "He (the man) complained to the Messenger of Allah ﷺ that during his prayer, he feels that he has passed gas, so he said: It does not nullify the prayer until he finds a smell or hears a sound."  

أَنَّهُ شَكَا إِلَى رَسُولِ اللهِ ﷺ الرَّجُلُ يَجِدُ الشَّيْءَ فِي الصَّلَاةِ يُخَيَّلُ إِلَيْهِ أَنَّهُ قَدْ كَانَ مِنْهُ فَقَالَ لَا يَنْفَتِلُ حَتَّى يَجِدَ رِيحًا أَوْ يَسْمَعَ صَوْتًا  

"A complaint was made to the Prophet about a man who sensed something (some doubt about his ablution) during prayer. He said: 'No (he does not have to perform ablution) unless he notices a smell or hears a sound.'" (Using translation from Ibn Mājah 513)  

شُكِيَ إِلَى النَّبِيِّ ﷺ الرَّجُلُ يَجِدُ الشَّيْءَ فِي الصَّلَاةِ فَقَالَ «لَا يَنْصَرِفْ حَتَّى يَجِدَ رِيحًا أَوْ يُسْمَعَ صَوْتًا»