No such issues with me on three, have you checked to see there are no issues with your local mast. I've got 4g now with three and it's excellent.
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Phone: Samsung Galaxy S4 I9505
Rom: DjeMBeY XXUFNC9 4.4.2 | Der Kernel: KT Kernel | Theme: Domination V2.0
Tablet: Nexus 7 2013 32GB
Rom: OmniRom 4.4.2 | Der Kernel: Stock Omni
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