Sound can be deceiving. Over time your hearing “comfort level”adapts to higher volumes of sound. So what sounds “normal”can actually be loud and harmful to your hearing. Guard against this by setting your equipment at a safe level BEFORE your hearing adapts.
To establish a safe level:
a.Start your volume control at a low setting.
b.Slowly increase the sound until you can hear it comfortably and clearly, and without distortion. Once you have established a comfortable sound level, leave it there.
22. Precautions
1). When not using the player for an extended period of time, please charge the battery at least once per month to extend the battery life.
2). Do not use the player in extremely hot, cold, dusty or damp environments.
3). Make sure the keys are unlocked before using the player (otherwise controls will not function).
4). Avoid dropping or striking the unit .This may cause external and internal physical damage to the player.
5). Charge the battery if:
a)The battery level icon displays 
(An empty battery)
b)The player powers off automatically and off again when restarted.
c)No response when pressing keys with keys unlocked and battery installed
6).To prevent damage from static shock, never use the player in very dry conditions.
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