So you gave them serial number etc and they haven't replaced it??
Strange as i thought from the serial number they could tell where and when it was purchased.
Also if its under guarantee why not get onto where you purchased it from, they should be able to help you out.
Yes i gave them the p/n, m/n, i just read that the warranty is 3 years on them this one is under a year.
I bought it from here.
I wanted to test logitechs customer support.