Update=installing the last version of BIOS and other updates resolved the issue
We have brought 5 Dell Precision 5560 of which 4 of them wire earphone does not work, the reply we got from technical support is that we need to update the driver. However even when dell technician was onsite he can't fix the earphone issue.  With regard to the rebooting issue, we have send one of the note book back to dell for testing, after 3 weeks they can see the issue however they can't resolve it and now dell tell us that it is a window update issue, it is not their problem.  Can some one help me with this?  
Dell Precision 5560 keep rebooting and wire earphone does not wrok