Cubox optical output cables wont fit due to poor case design

Has anybody tried to plug an optical cable into the Cubox I4. You will find that many standard optical cables do not fit due to the square hole in the case being too small. The round outer casing of the optical cable simply will not fit and I do not want to cut the case on my Cubox. This is very bad design and needs to be rectified ( I have 3 different brands of optical cable and not one will fit. Also be aware that the WIFI range is hopeless and it simply wont connect in the room that I want to use it in. Every other device that I have connects fine including a Raspberry PI with a small Edimax Wifi dongle.
I am dissapointed to say the least and will consign my Cubox to a KODI media centre in another room.