Makhul used to recite Surah al Fatihah al-kitab quietly in the prayer in which the imam recites the Qur’an loudly when he observes the period of silence. If he does not observe the period of silence, recite it before him(i.e before his recitation), or along with him or after him; do not give it up in any case.
مَكْحُولٌ اقْرَأْ بِهَا فِيمَا جَهَرَ بِهِ الإِمَامُ إِذَا قَرَأَ بِفَاتِحَةِ الْكِتَابِ وَسَكَتَ سِرًّا فَإِنْ لَمْ يَسْكُتِ اقْرَأْ بِهَا قَبْلَهُ وَمَعَهُ وَبَعْدَهُ لاَ تَتْرُكْهَا عَلَى حَالٍ