51AppendixFAQ and troubleshootingThis section lists frequently asked questions that may arise during the use of yoursmartphone, and gives easy answers and solutions to these questions.Aspect Question AnswerAudio Why is there nosound coming fromthe device?If the headset is plugged into the device,the speaker is automatically shut off.Disconnect the headset.Check that the device volume setting isnot muted.Check that the volume control is not at itslowest setting.Multimedia files Why can’t I view myvideo files?You may be trying to view a video that isnot supported. Refer to "Multimedia" onpage 56.Why can’t I play mymusic files?You may be trying to play a file that is notsupported. Refer to "Multimedia" onpage 56.Systeminformation andperformanceHow do I check theOS version of mydevice?Tap Settings > About phone to checkthe OS version (Build number) and otherhardware and software information.Power I can’t turn on thedevice.The battery power may be depleted.Recharge the device. Refer to "SIM cardlock" on page 8 for more information.RAM / ROM How do I check theRAM and ROMmemory status?To check the ROM status, tap Settings >Storage.To check RAM status, tap Settings >Apps > RUNNING.Internal storage My device’s availableinternal storage is fullor almost full.Uninstall apps to increase availablestorage. See "Uninstalling an app" onpage 46.