But there are some cases where you just want to run to a certain slide, instead of running the entire slide, you have to adjust differently.
You must first insert the audio file into the slide you want to start running, then go to the Animations tab -> select Animations Pane
The Animations Pane tool dialog box will display to the right of the powerpoint, click the downward triangle in the inserted audio file and select Effect Options .
Here you will select From beginning (slide you insert audio file) until the slide stops audio, select the number of slides in the After section
Click OK to complete the setup, but you also have many other options in the Audio Tools section that Powerpoint supports.
For Powerpoint 2003 version, you will go to Slide Show menu -> Custom Animation and edit the same as above