Nextar MA750 - Manual (Page 43)

5.8.4
5.8.5
Record Type
Press rewind button or fast forward button in Record Type setting
menu to select recording format and press play button  to confirm.
Long press play button  or press power/stop button to skip this
setting. This setting is used to set the sampling rate of microphone
recording. The available recording formats for this player are: 8KHz,
11KHz, 16KHZ, 22KHz, 32KHz, 44KHz and 48KHz.
Contrast
Press rewind button or fast forward button in the contrast setting
menu to select contrast and press play button  to confirm. Long
press play button  or press power/stop button to skip this setting.
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