Hi cikguzara,
Welcome to Sony Community!
We're sorry for the inconvenience. Since you already did all the troubleshooting and did a factory reset but the issue persist then more likely this is a hardware issue. I strongly suggest that you bring the unit to an professional repair center to have them fix it.
For further assistance regarding your concern, please contact the Sony offices/Sony representative offices nearest to your place of residence in Asia Pacific region http://www.sony-asia.com/countryselector.html?hpid=countryselector:AsiaPacific. Due to proximity, they are in a better position to respond to your questions or concerns.
Regards,
Jen
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