i've had the same problem with the mini usb charger.
i've been to carphone warehouse(from where i bought the phone) and today (06.08)after almost 3 weeks i have taken my phone back repaired under warranty but it camed broken 
now i have another problem(it worked fine before i was to cpw) it seems that i have lost the "32 gb memory" ...i'm getting this message"memory card format unsupported"
i will send it back but anyone knows where should i go 'cause i don't want to wait again 3 weeks to get my phone fixed(i have tried to reflash it but still i have the same problem)
any advice ? where should i go to my phone?
posted this on the maemo forum, and have been advised to post here
this was what I have posted.
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Been lurking around here for awhile learning about my N900....
But sad to say my new N900 I bought less than 3 months ago has it's USB port broken off.
I returned it to my phone service provider (Optus) and after 2 weeks waiting, I have been told today the phone is "Physically damaged" and will not be covered under warranty. After much to and fro, I have been advised to call Nokia, in which Nokia customer service assured me it will be covered under warranty... They even gave me a reference number to give the local Nokia customer service center.... I was pretty happy with the outcome
After driving close to 30mins to my nearest service center (only one in Perth, W.Australia), the service girl had a look at it, brought it to their tech guy, and came back telling me its a "Physical Damage" and wont be covered under warranty. I replied by telling her I have read in a few internet forum (including here and Nokia) that the USB breaking is a known issue among N900 users. her reply was: "Dont believe everything you hear on the internet" .... not happy
Her suggestion to me was the only way to fix the phone is to replace the board. and by doing so, the cost out of my pocket will be nearly the same as buying a new phone.... so.... she told me "Go buy a new phone".....
Unfortunately, after many years of using different mobile phones, I never had any hardware failures like this... ever... pretty disappointed with the quality and customer service.
As I am still under contract with Optus (21 months left), it was fortunate Optus Customer service is willing to help out (even though I dont have phone insurance) by reducing some of my costs in getting a new phone.
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Unfortunately, the Australian Nokia care service are not aware of the issues with the broken USB problem, and seems like they are still using the "User Error" response. Im sending in my N900 tomorrow again, but this time round the assesment will be documented (as I found out the first time I brought it to the care center, they didnt document the assement of physical damage)
It is extremely frustrating that Nokia is not communicating this issue to all care center, the lack of empathy when discussing the issue with the service support people. Sadly, Nokia care doesnt take this forum seriesly, as I have mentioned that it has been posted here by different users, and with Nokia's response.... they still dont care
and to consider I just found my Sony Ericson P900 I had since 2003/4, after heavy usage, and overnight recharge, I can use it with no issues ... my GF is using my old Iphone 3 I had for 2.5 years with no issues. I find it highly insulting to hear a reponse of "It has passed the QA test of your store, so it must be your fault"
With under 5 months careful use the USB became loose on my N900 and the USB charging and data stopped. I believe that Nokia would fix this under warrently, but sending the handset off and potentially getting a replacement/recondition handset returned.
Foolishly I only had a very old backup and without the means to either charge or take a backup I did not want to loose everything on my phone. I went to a local Nokia Repairer and they re-soldered the USB socket back onto the board and was fixed the next day for 25UKP. Worth it to avoid loosing my data and spending many hours 're-building' my phone back with all my apps etc.
I am now filing down the lugs (protrusions) on the micro USB plugs to ensure they pull out with minimum force.
I will also be taking regular backups !! and I advice all phone and PC owners to faithfully take backups - a few minutes each week to start off a backup and protetc your data/appa is well worth it !
OMG!
this has to be a record!
just checked the status of my device, it was actually input into the system the same day it was recieved! and already shows shipped replacement!
usually takes at least 2-2.5 weeks. i just may have it before the weekend depending on if it actually went out today...being that monday is a holiday in the USA, i hope it gets here before the weekend.
(i miss my speed!!! back on my e90, only 2.75g on Tmo.)
heck, i am so excited about Nokia doing this so fast, ima share some kudos with the nokia reps on this blog! 
Repair History:
| Current Status | Shipped Replacement Phone |
| 08/31/10 | Received |
can u tell me how long did u wait till you got your replacement N900 back. I missed my phone like tonesss!