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UC923/UC924(E)/UC926(E) nned need to upgrade the fw920M.rom
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UC923 upgrade the fw923.rom, UC924 upgrade the fw924.rom, UC926 upgrade the fw926.rom.
If the DSP parameter of the phone with "D", then
UC926U/UC926S/UC924U/UC924W/UC923U/UC921U need to upgrade the fw920U.rom
For the new models
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