I have three sets of RT5's and after setting them up in my new home one of the speakers mids would not play. The tweeter plays fine but nothing from the mid. After having it checked out, I was told that the voicecoil had gone out. I tried all the other speakers in the same location and they all played fine. I was told to replace the mid and the problem would be solved. Does this sound like good advice???
Yes, it does.
Apply even pressure to the mid-woofer, in other words, try to push it in a little, with your fingers splayed.
Lightly press the woofer cone, back and forth.
If it "scrapes" or makes a odd sound, replace. Blown driver, easy fix.
It should be smooth upon even compression.
If the action is smooth, replace with the another driver(e.g. your other speakers' mid-driver) and test the same media.
We can get more in depth...more than likely, bad driver.