Why is my carkey loosing range

Hi,

i noticed that the remote in my key loses range. So i changed the battery, but that didn´t help. I´m still loosing range. Any ideas how to fix it?

The key looks like the one in this thread, the original electronic is shown on the right hand side.

http://www.audifieber.de/audiforum/threa...

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0