I have a Hohner accoustic bass guitar with a piezo/ceramic pickup in the bridge. (The fat kind) The G string has lower volume than the other strings. (I've tried many sets of strings) I've taken it apart and the pickup has a single element with no sign of any reason why one end would be quieter. Has anyone else had this problem? Has anyone had any luck fixing it or using some sort of sound-hole pickup instead? The instrument is inexpensive but sounds decent acoustically. Any suggestions would be appreciated.