question about an instance of "durchkommen"

[edmont]

Context: the lecturer referred to in the German sentence below is being heckled by some of his audience. 

Question: Does "schwer durchzukommen" mean it was hard for the lecturer to get through to his audience? Or does it mean it was hard for the lecturer to get through (i.e., to complete) the lecture?  Thank you very much for any assistance.

Hans hatte es schwer durchzukommen, führte aber den über eineinhlbstündigen Vortrag mit kraftvoller Stimme zu Ende.

[tiorthan]

I would say it's having a hard time completing the lecture but it's not entirely clear here.

[edmont]

Thank you very much, tiorthan.