[beachgeek]

I searched but could not find a thread for modifying ms1i to a balanced input.  I have an extra set with problems in the right ear, so thought this would be perfect for that set.
 
Anyone done this?

 

[Drubbing]

If they're faulty, balanced input won't fix it - balanced simply provides a dedicated signal of given polarity to each driver. The aim is to reduce (often theoretical) noise from amps, not something an MS1 is going to have much issue with.
 
Aside from that, the cost alone wouldn't be worth it. That's probably the reason there's no threads on it.

 

[KingStyles]

What type of problems re you having. Grattle happens quite a bit on ms1. If it is grattle, just cup your hands around the driver and suck until you hear a pop. Otherwise youmight just want to take the cover/cup off and make sure everything is alright inside. I have balanced a set before. It did seem to help the bass region a little. More bass presence and less flab. Just like doing any other can. Cut the plug and solder on the balanced plugs. I made mine into ms1000. Here is a picture and a few threads that might be helpful.
http://www.head-fi.org/forum/thread/431493/balanced-xlr-conversion-howto-grado-gs1000
http://www.head-fi.org/forum/thread/461915/a-pic-by-pic-grado-sr80-recable-thread
Here is my balanced ms1/ms1000