The decision was taken at the 242nd syndicate meeting with IU Vice-chancellor Professor M Harun-Ur-Rashid Askari in the chair at his resident around 9:00 pm.
The two professors are associate Professor M Baki Billah Bikul of Bangla department and Professor M Shahadat Hossain Azad of English department of the university, said IU acting registrar SM Abdul Latif.
They were asked to submit their replies within seven working days, he added.
Necessary legal steps would be taken after getting responses from the teachers, he added.
On July 15, a total of four audio clips containing conversations between several candidates and the two teachers for appointing one of them as a teacher in the History and Culture department was leaked and went viral on the social media.
Later on July 16, the university authorities suspended Professor Azad from the post of provost of Bangabandhu Sheikh Mujibur Rahman Hall and Assistant Professor Bikul from the post of director of Birshrestha Hamidur Rahman Auditorium.
The authorities also formed a three-member probe body headed by IU Business Administration faculty dean Professor Arabidu Shaha to investigate into the matter.