Mackie FRS-2800 Owner's Manual - Page 13

Owner's Manual One side is louder than the other Repair • Are both level controls set to the same position? • Check your source signal to make sure the left and right signals are balanced. • Are the speaker impedances matched? Different speaker loads can cause different volume levels on each side. • Try switching sides: Turn off the amp, swap the speaker cables at the amp, turn the amp back on. If the same side is still louder, the problem is with your speaker cabling. If the other side is louder now, the problem is with the mixer, the amp, or the line-level cabling. Poor Bass response For warranty repair or replacement, refer to the warranty information on page 19. Non-warranty repair for Mackie products is available at a factory-authorized service center. To locate your nearest service center, visit www.mackie.com, click "Support" and select "Locate a Service Center." Service for Mackie products living outside the United States can be obtained through local dealers or distributors. If you do not have access to our website, you can call our Tech Support department at 1-800-898-3211, MondayFriday, 7 am to 5 pm Pacific Time, to explain the problem. Tech Support will tell you where the nearest factoryauthorized service center is located in your area. • Check the polarity of the speaker cable connections. You may have your positive and negative reversed at one end of one speaker cable. As the music gets loud, the amp shuts down • Make sure the OL LEDs are not lighting continuously. If so, turn down the signal source or the amp level controls. • Can the amp breathe? It needs plenty of fresh air to stay cool. Do not block the ventilation holes. Noise/Hum • Check the signal cable between the mixer and the amplifier. Make sure all connections are good and sound. • Make sure the signal cable is not routed near AC cables, power transformers, or other EMIinducing devices. • Is there a light dimmer or other SCR-based device on the same AC circuit as the amplifier? Use an AC line filter, or plug the amplifier into a different AC circuit. • If possible, listen to the signal source with headphones plugged into the console. If it sounds noisy there, the problem is not in the amplifier. • Is there a cable-TV audio feed in your system? An incorrect ground may causes a "ground loop" hum. • Sometimes it helps to plug all the audio equipment into the same AC circuit so they share a common ground. Owner's Manual 13