First of all, Hu Jun's role in the battle of Changjin Lake is the father of Lei of Jiulian Company. Dad ray is one of the most important characters in the movie. His hometown is Yimeng mountain area, but according to Wu's account, Lei's father basically has no relatives or friends in Yimeng mountain area. After Wu Baili, Wu and Wu joined the army, they were all brought up by Lei's father. Therefore, Lei's father is his teacher and friend.
Secondly, it is precisely because the role of Dad Lei is plump and a typical soldier image that we don't need to care about his singing skills or even the artistry of his singing skills. When the role of Dad Lei died, he was still humming Yimeng Mountain Minor. Judging from the plot, this song is actually only used to highlight Lei's father's yearning for his hometown, and then set off the tragic and desolate atmosphere when Lei's father died. So Hu Jun's singing is just this function, and no audience will care about Hu Jun's singing.
Finally, Hu Jun also sang "Yimeng Mountain Minor" in an interview afterwards, but his voice was still inaccurate and his breath was erratic. Considering his singing skills from the professional level, he basically failed in every item. But Hu Jun is an excellent actor, and he has no plans to enter the music circle, so Hu Jun doesn't need to care about his singing skills at all.