Does Viral Audio Feature BR Ambedkar's Voice? A Fact Check

An audio clip is going viral online to claim that it features Dr Bhimrao Ambedkar's speech at the Second Round Table Conference that happened in London, United Kingdom in 1931.

An audio clip is going viral online to claim that it features Dr Bhimrao Ambedkar's speech at the Second Round Table Conference that happened in London, United Kingdom in 1931.

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But the truth is...: This voice belongs to a Malayalam actor Mammootty, who portrayed Dr Ambedkar in the 2000 biopic Dr Babasaheb Ambedkar.

How did we find out the truth?