音频单元未声明的标识符

我正在尝试使用这2个链接中的代码(大致相同的 LINK1 LINK2 ).但是，即使第二个链接是Apple Prog指南，也无法使用.

Im trying to use code from these 2 links (pretty much the same LINK1 LINK2). But neither work even with the second link being an apple prog guide.

就像我说的那样，实际错误是许多数据类型上的使用未声明的标识符".为了使它简短一点，我将仅显示前2种数据类型.

Like I said the actual error is "use of undeclared identifier" on many of the data types. To keep this a little shorter I will just show the top 2 data types.

 AudioComponentInstance audioUnit;
 AudioComponentDescription desc;

根据搜索结果，这些应该是

From the searching I have done these should be this which says they are in the AudioUnit framework. AudioUnit.framework is added to my "link binarys with libraries" so I dont understand why these data types are not found.