I take it you have tried a different headset?
you can always call 789 and go through virgins diagnosis and get them to repair it, but to it may not be a faster option, also I'm sue if virgin were aware when the contract was placed with Sony they would not have bought them.
Sorry to hear about the issues you've been having with your handset.
Just over to our Phone Fix page here to run through some diagnostics.
If we need to repair the phone for you, the good news is we aim to have the phone back to you within the week, so you won't be without it too long!
Please let us know how you get on.
Mark YForum Team
Need help changing SIM card? Find out more about activating your 4G ready SIM. 4G SIM Swap Help