Nexus S echo problem - a dead simple solution

The Nexus S can have a slightly annoying echo problem during calls.

It's really easy to fix, I'm kicking myself I didn't try this earlier...

1. take the back off your phone
2. grab some printer paper, (a slightly heavier weight is better)
3. cut out a piece which is big enough to wrap around the battery
4. fold this piece over three times
5. place on top of the battery
6. replace the cover
7. enjoy!

I used the same trick with my N95 when the battery used to come loose