The little metal strip that regulates the volume control for calls has come off.....if they can't repair it do you think they will be ok with replacing it? I only bought it today.

IIRC Cex phones come with a 12 month warranty

See here for further info

Is there a warranty on items that I buy from CeX?

Yes, CeX offer a 12-month warranty on all products excluding consumables.

This warranty covers all faults arising during the course of normal use, and does not cover physical damage or water damage. Please view our Terms and Conditions for further warranty details.

If your item develops a fault and is covered under our warranty, please follow the details in our returns procedures[listed below]. Please note that repairs under warranty can take up to 28 working days.

http://uk.webuy.com/help/