Where exactly is it in the control room? I've looked around and have yet to pinpoint its location.

I do think that there may be something wrong with radars in S-class subs. For example, if you install the SD radar in a S-class, the radio keeps playing even when you have turned it off. Also, in other subs the radio only works on the surface (dive and the sound goes away), but in S-class subs the radio keeps playing submerged.

Anyone else noticed this?

Yes i have noticed the radio keeps playing submerged in an S-class . I wonder if this could be fixed by a modder .