Step 1: Download trial version of Movie Player Gold ActiveX and installed it.

Step 2: Download sample mpeg1 file from here

Step 3: Run Decoder Filter Sample, and select playback sample mpeg1 file.

Step 4: If your computer have not installed third party decoder, you should see MPEG Audio Decoder loaded (left size), the screen as following

Step 5: Try download ffdshow and installed it .

Step 6: Close the decoder filter sample and run it again, Select playback sample mpeg1 file.
Now you will see ffdshow Audio Decoder loaded. the screen as following

When multiple decoders are available, Windows uses the Intelligent Connect algorithm to select the decoder, so some media file cannot playback correctly or not sync in some user computer.
Another test, we try select playback vob file, the ffdshow Audio Decoder will loaded automatically,instead of Viscomsoft MPEG Audio decoder, for this situation, audio may not sync.
In this case, if you need call SetMPEG1AudioChannel method, now it will not work. because MPEG Audio Decoder have not loaded.

Step 7: Now we want to bypass ffdshow Audio Decoder, you may add following code

MoviePlayer1.UseDecoderFilter = True
MoviePlayer1.DecoderFilterType=2
MoviePlayer1.DecoderAdd2BlackList "ffdshow Audio Decoder"
MoviePlayer1.FileName ="c:\mpeg1sample.mpg"