Does the M80 cable sit securely in there, even without engaging with the locking mechanism? If you have chance, could you give me an idea of the diameter of the jack you've had success with? Is the retaining clip spring loaded (ie could be jammed out of the way) or is it a single bit of plastic?
Sorry for all the questions, trying to decide whether to get these or the dt770... Easily replaceable cables without modding could be a plus.