OK here's the saga.

My iPhone 4S recently developed a fault whereby it switches itself off around the 40% battery mark and wont switch back on again unless plugged into a power source. This is my work phone and I work on 24/7 call a lot of the time so this is a major issue for me.

Anyway, I performed a factory reset on the phone and gave it a full charge but the problem still occurred. Took the phone into Telecom who sent it to Telegistics. Telegistics reported that they were able to replicate the fault so guess what - they did a factory reset and sent it back.

The day after getting the phone back, phone gets to the magical 40% battery and boom, switches off and wont switch back on. Took it straight back to Telecom and showed them that it wouldn't switch on and then plugged it into a power source and showed them that it still had 40% battery showing. They sent it back to Telegistics.

This time Telegistics perform 4 battery drain tests - I'm guessing they used a tool for this and its wasn't just left to drain itself - They reported no fault found and sent it back.

I got the phone back yesterday and this time just to be sure it wasn't any of my apps or settings, I didn't make any changes to the phone apart from putting the SIM in and activating so I could receive calls and TXTs. Guess what happend :-)

This morning the phone has switched off and wont switch on. Plugged it in and hey presto 38% battery showing.

So now I have been without my iPhone for 2 weeks, have had to spend my time waiting to talk to someone at the Telecom store twice and had to use a dumb loan phone instead of my $1000 iPhone!

What can I do? Can I go thermo-nuclear in store and demand a new phone -will that get me anywhere? If I'm forced to send it away and Telegistics testing still shows no fault, what are my options then?

Any help appreciated.