I don’t know if this will be of any help, but the PDF manual for the Mountbatten Brailler includes tips to reduce the noise level of the Brailler:
- Put the Brailler on two computer mouse pads. I suppose any thick foam pad would do.
- Turn down the braille pressure.
- Place the Brailler in front of a solid object such as a book or facing a wall.
You could also put the Brailler under a frame covered with heavy furniture moving blankets, a kind of “Kitchen Table Sound Studio” as described by kozikowski in this very forum at https://forum.audacityteam.org/t/too-compressed-rejection/52825/22
HTH
Robert