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"For a fact it is known that majority of Galaxy Nexus phones seem to suffer from a 'SAV Ghost' or 'Volume Bug', where the device volume is automatically adjusted (usually lowered, but not always) when it gets radio interference from itself or a nearby device, that is transmitting on 2G and GSM 900 (900Mhz).
It is very common for the device to lower its volume during phone calls on 2G network or when using 2G data. While it does not only happen during data connection, one can detect phone itself causing interference When the phone itself is using 2G data by the icon E (for Edge) or G (for GPRS) and volume rapidly changes while that happens.
Problem is worse when the phone is on low-signal area and thus uses the radio more frequently to find or hold on to the signal.
2G networks working on GSM 900 are majority of Europe, Africa, Australia, Middle East and large part of Asia. GSM 900 however is not existent on US and Korea networks, where the device might have gotten majority of its testing. In UK, the GSM 900 is used by O2, Vodafone, giffgaff, Tesco Mobile.
This problem happens even if the radios of the Galaxy Nexus smartphone are turned off and even when the device is not running Android 4.0 itself, so the problem is not in Google's software. Device is known to have this problem even while in bootloader, the lowest environment it has been detected in.
While the problem exists, device is often unresponsive for a short time, dealing with a lot of 'input' at the same time.
The above reasons mean that the problem exists in hardware level of Galaxy Nexus smartphone and if you suffer from this problem, then you have a faulty device.
It is still unclear if all Galaxy Nexus smartphones suffer from this issue. A lot of users do not use 2G networks or have used them so rarely, that the problem as possibly slipped by unnoticed as nothing more than a inconvenience.
Samsung UK definitely released a large number of affected phones in UK last week, these devices are the ones that users are reporting problems with. Replacements of the device so far haven't worked for most users.
Pre-release phones however did not report this issue. This may be because pre-release phones did not have this issue and Samsung released - possibly unknowingly - a faulty batch of handsets in UK. It is also possible that pre-release phones simply did not look out for the existence of the bug and did not test the 2G network, instead testing the device on WiFi or non-GSM-900 networks.
Some sellers report that Samsung has conducted additional testing on devices that were delivered to SIM-free sellers for this week. Whether this means they detected the problem in previous batch or not, is unclear. So far Clove and Handtec haven't been able to reproduce the problem on phones that were delivered to them.
Whether Galaxy Nexus is flawed by design and all devices are affected, or this was a result of a broken batch, will be clear within the next few days as SIM-free phones are being delivered to fulfil pre-orders.
If new SIM-free deliveries are not affected by the problem, then the only affected phones were the ones released in UK, and Samsung will likely simply have to replace the problematic handsets in the market.
If new SIM-free deliveries are also affected, then it is likely that all Galaxy Nexus phones manufactured so far are affected by this issue. This might lead to mass-recall of the devices and further postponement when it comes to the handsets release.
One alternative is that Samsung might release a software update that does not fix the hardware problem - as this is not possible - but will alleviate or ignore the issue so it does not affect general use of the phone. Problem will still exist, but it would be less noticable or get in the users way less.
We will see what the next few days tell us."