The actress is making her West End debut in the Anton Chekhov play, and she took to the stage for the run's first night at the Vaudeville Theatre in front of a star-studded audience on Friday (02Nov12).
Hall was among the crowd and rumours later surfaced suggesting he took the attention away from Carmichael's emotionally-charged finale by heckling her performance.
Now the theatre mogul has addressed the reports, admitting he fell asleep during the show and shouted out in shock when he was woken by his wife.
In a statement, Hall writes, "I am mortified that I unintentionally disrupted the final scene of Uncle Vanya and I have sent a personal note to Laura Carmichael offering my apologies.
"I enjoyed the evening, and her performance, immensely, and I cannot stress too strongly that my remarks were in no way directed at her or the production.
"Being rather aged I dropped off for a moment and on being woken by my wife I was briefly disorientated. Remarks made in the resulting confusion were not in any way related to Uncle Vanya which I think is a very fine production with a marvellous company of actors."