Here I would like to consider the intercom function in the lab (see Szendeffy, 2005, p.21). A high school for which I used to work had this device in its language lab. Four years ago, I was interested in using this function just because it looked fun. When I used this in my class, I realized it can be hazardous if it is used without considerations. They became excited as I had expected, but they started talking in Japanese. Even worse, in order to enhance the excitement, I had connected students at random so that they could start with guessing and asking whom they were talking to. I had 36 students in the class, so it was exhausting to calm them down. I am still wondering how we can effectively use this device in EFL settings where students tend to use their native language when teachers look away from them.
I used to think technology could be used just because technology itself was exciting enough to raise students' motivation. However, I realized that I was wrong at this point.
Szendeffy (2005) posits a question about the intercom device "[Teachers who like to use this device] want students, even those sitting next to each other, to be able to communicate verbally through headphones attached to the computers. … How would this ability enable to richer language experience than having these students talk face-to-face?" (p.21). I will provide here an example for this question. For ESOL, telephone conversation is one of the challenges which they are likely to encounter. Since this type of conversation does not allow interlocutors to read gestures, communication requires accurate pronunciation and listening proficiency. Intercom device allows a lesson to practice this situation without using (and even paying for) real phones.
Reference
Szendeffy, J. D. (2005). A practical guide to using computers in language teaching. Ann Arbor, MI: University of Michigan Press.