What kind of guitar and pickup are you using? Have you adjusted the master gain?

First adjust the master gain: https://support.tonewoodamp.com/support/solutions/articles/17000016254-adjusting-the-master-gain-video-

If you have, try the notch filters. You can find a video and instruction on that here: https://support.tonewoodamp.com/support/solutions/articles/17000024241-notch-filters-video-