Data locked when switching from 4g back to 3g

[rob1982]

Recently purchased a new HTC One M9 from Carphone Warehouse on O2.

Fairly happy apart from patchy signal by my house despite O2 coverage checker showing full 3G and even small pockets of 4G.

My main issue is that for some reason when I go from a 4G connection back to 3G despite the phone showing a decent signal nothing that requires a data connection will work.

To resolve this I simply have to go in to airplane mode and back out again.

This is not ideal as I commute a fair distance on a daily occurance so this has to be done multiple times throughout the day.

I'm not convinced this is an O2 issue though as I had the same issue with my initial purchase of the M9 through Vodafone, due to terrible signal everywhere I went.I took that phone back and replaced it with one on O2.

Has anyone else experienced this or know of a more permanent solution?

[perksie]

Does turning 4G off help?

Have you checked for signal problems in your area?

http://status.o2.co.uk/

[rob1982]

I've just checked on O2 status and it does report that there have been works carried out on the masts near my post code in the last 24 hours but says the network is currently working fine, this may explain why the signal has been a bit patchy.

As for the "data locking" I've been experiencing, I have not tried turning off the 4G connection, I will try doing that and comment after my commute home today.

Thanks

[rob1982]

Well I turned 4g off ready for my train journey home.

Turns out it had an improvement, the only time I lost connection is where it was expected and I had no signal whatsoever or dropped to 2g (pretty much the same thing).

Signal is still poor by my house so I think the network status check might have lied about everything running smoothly.

Not sure what to do about my 4g though as I want to get it turned back on for obvious reasons.

[Anonymous]

http://forums.androidcentral.com/htc-one-m9/532414-m9-problems-when-4g-transitioning.html

http://forums.androidcentral.com/htc-one-m9/526486-why-can-t-i-send-text-messages-4g.html

You are not the only one....but couldn't find an answer anywhere...

Any ideas @viridis, @MI5, @Bambino, @jonsie...?

[MI5]

I used to get this occasionally on Kit Kat but I've not experienced it on Lollipop, however, it's most likely a bug in the phones modem software.

[rob1982]

Thanks for your input.

It would be a bit of a concern for M9 owners if the problem is with the modem software as I have had x2 M9s now with the same issue which could suggest a build issue.

Would be interesting to know if this happens on rooted phones or even international variants.

[Cleoriff]

@MI5 is the one to answer this query @rob1982

[MI5]

Rooting a device would not change the modem so unless a different modem was flashed the issue would still be present.

[rob1982]

Basically I'm not getting rid of this problem am I?