This is what the tech wrote:
Car programs OK. Tested sounds works properly. Shut power off and restarted multiple times. Sounds not starting up every time. Checked several wire connections. Found loose wire harness - Replaced wire harness - sounds operating properly. Test ran for 3 hours without issue.
I don't have the previous repair notes with me. I do remember that they replaced the soundboard and the pick up connections.
J Daddy - I totally agree with you. Unless there quality control procedure can detect every flaw, or defect which I highly doubt they should always produce more units for problems like this.