Orange/EE don't carry the One X + unfortunately or I would definitely see if I could. I don't think there are really any comparable phones apart from the SGS3 which I have a funny feeling they will say isn't eligible. I remember I had this before with my Motorola DEXT back in the day and I wasn't able to top up with any cash either to get a better handset but I swapped it for the Hero and been with HTC since.
EDIT: So handset number 4 arrived, another SH24. Turned it on and checked the wifi and low and behold it has exactly the same problem fresh out the box. Called Orange immediately so should get another one tomorrow. This is so frustrating! It's really bad where I am because as the router isn't in a convenience place, I can't use the wifi in my house. The build quality is pretty bad on this new one as well. You can barely see the LED behind the speaker.
After sending you out another faulty phone, it's got to be worth an ask its the least they could do, assuming you like the s3.
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