[. . . ] For more than 50 years, JBL has been involved in every aspect of music and film recording and reproduction, from live performances to monitoring the recordings you play in your home, car or office. [. . . ] Wiring "out of phase" results in thin sound, weak bass and a poor stereo image. RIGHT LEFT ­ + ­ + ­+ ­+ Speaker Outputs Troubleshooting If there is no sound from any of the speakers, check the following: · Receiver/amplifier is on and a source is playing. If there is no sound coming from one speaker, check the following: · Check the "Balance" control on your receiver/amplifier. · Check all wires and connections between receiver/ amplifier and speakers. If the system plays at low volumes but shuts off as volume is increased, check the following: · Check all wires and connections between receiver/ amplifier and speakers. [. . . ] 9/98 Part No. : D38, D315OM We, JBL Europe A/S Kongevejen 194B DK-3460 Birkerød DENMARK declare in own responsibility, that the products described in this owner's manual are in compliance with technical standards: EN 50081-1:1992 EN 50082-1:1992 © Steen Michaelsen JBL Europe A/S Birkerød. [. . . ]