Sony VGC-V520G - Manual (Page 47)

Do not mix old (used) and new batteries when replacing batteries in the remote control. Always use the
same type and manufacture of battery — do not mix alkaline with manganese batteries. Using incompatible batteries
or mixing used, new or different types of batteries can damage the remote control.
If your remote control does not operate properly, the batteries may need to be replaced. When your remote control is
not being used for extended periods of time, remove the batteries to avoid possible damage from battery leakage.
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