Auto-Tune Pro 9 is a widely used pitch correction software that can help musicians, producers, and engineers adjust the pitch of recorded vocals. However, one issue that users may encounter is that Auto-Tune Pro 9 may not work correctly when the recording is not on a standard pitch frequency.

The reason for this is that Auto-Tune Pro 9 is designed to work with specific pitch frequencies, and when the recording is not in the standard frequency, the software may not be able to accurately identify the correct pitch, leading to ineffective or incorrect pitch correction.

To ensure that Auto-Tune Pro 9 works correctly, it's essential to make sure that the recording is in the correct pitch frequency. This can be achieved by either re-recording the vocals at the correct pitch or by using a pitch shifter tool to transpose the recording to the correct pitch frequency before applying Auto-Tune Pro 9.

It's also important to note that Auto-Tune Pro 9 is not a replacement for good singing technique. While the software can help correct minor pitch issues, it cannot compensate for poor vocal performance or technique. Therefore, it's essential to work on developing good singing skills to get the best results from Auto-Tune Pro 9.

In conclusion, Auto-Tune Pro 9 is a powerful tool for correcting pitch issues in vocal recordings. However, it's crucial to ensure that the recording is in the correct pitch frequency before applying pitch correction. With the right approach and technique, Auto-Tune Pro 9 can help take your vocal recordings to the next level.