Silence a microwave with simple panel

I would like to mute the beeping on a Sharp 75MR microwave. I have read that many microwaves can be silenced by holding the 1 or 0 button, or with secondary keys, but this has a very simple panel with only 10 minute,  1 minute and 10 seconds buttons, plus some pre-sets. Holding the number or pre-set keys does nothings, and holding stop activated the child lock.

It came with my employer-provided accommodation, so I’d rather not do something permeant to it, but I’ll disconnect the speaker if that is the only option. The manual has nothing on this topic.

Thank you