китайці знають англійську гірше за мене, але можливо щось вдасться з'ясувати з написаного ними =)
http://yatour.net/article/?type=detail&id=30" onclick="window.open(this.href);return false;
(6) OSD normal, silent or sound incomplete.
① check the CD host is the host of the volume gain is the smallest (ie, not open volume).
② check the CD host is transferred to the side of the sound field pattern (ie, adjusted to only use the left channel or right channel).
③ Press the CD button to switch functions on the host computer, switch to CD mode or the state of FM radio to see if the sound is normal, if not properly check the CD master.
④ Check SD or USB device:
A. check the SD card, USB device is not inserted firmly;
B. SD card, USB device, whether the music files;
C. check the SD card, USB devices, music or video file is formatted correctly (now disc box support for MP3 digital music format WMA and MP3, MP4 digital disc box supported formats are MP3 , WMA , MPG , AVI , DAT , VOB , DIVX , MP4 Such as video and audio, as well as JPG and other image formats).
Но вот новая заморочка - громкость звучания хуже чем радио или диски - только у меня так? или еще у кого-то такая же проблемка? 
