If you have installed previous version of ACS, uninstall it before installing the new version. Click Component->Install Packages menu item. In the opened dialog box select the Audio Components Suite package and click "Remove" button. Make sure to remove all the previous version files from the IDE search path.
To install Audio Components Suite, first compile the package. Create or select directory where you want the components to be installed (you can use your Delphi/Kylix lib directory). We will call this directory ACS directory. Now go to the Src directory of the ACS distribution, and copy all the files from either Linux or Win32 directory to the ACS directory. Copy all the files from the Common directory into ACS directory.  
Now go to the ACS directory, open ACS.dpk file in your IDE. Press "Options" button, in the opened dialog go to Directories/Conditionals tab and up set the output paths to the directory where you have copied ACS source files, press OK and then in the package window press "Compile" button. Click Component->Install Packages menu item. In the opened dialog box click "Add" button. Browse to the ACS directory and select the file called bplACS.so.2.2 (Kylix) or ACS.bpl (Delphi). After this two new tabs: "Audio I/O" and "Audio Processing" will appear on the components palette. Unless you have selected your Kylix/Delphi lib directory as ACS directory, you will have to add the ACS installation directory to the Kylix/Delphi libraries search path. This can be done on the "Library" page of the "Environment Options" dialog box (Tools->Environment Options... menu item).