Classe Audio CP-500 owner manual There is a hum coming out of the speakers

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5.There is a hum coming out of the speakers.

•If you are running single-ended interconnects, make sure they are not running alongside any AC power cords.

•If you are running single-ended interconnects, make sure they are not too long. Long runs of single-ended interconnects have a natural tendency to pick up noise even if they are shielded.

•If any source components connected to your preamplifier has a cable TV hooked up to it, try disconnecting the cable television line from the source. If the hum goes away, you will need an isolation device between your cable and that particular source. Refer to your Classé dealer for one of these inexpensive devices.

•If you have the optional phono module in your preamplifier, make sure that the ground wire of the tonearm is secured properly to the ground lug on the back of your preamp.

•If the hum exists only on the phono input, make sure the turntable/tonearm assembly is not too close to other components. There should be at least 12 inches (30cm) clearance from the other components. The more clearance you provide, the better (as long as the tonearm cable is not stretching).

•Make sure the tonearm cable is not touching or running alongside an AC cable.

•Make sure you have the proper loading for your phono cartridge. If you are in doubt, consult your authorized Classé dealer.

6.There is a mechanical hum coming from the unit.

•This symptom suggests you have a lot of electrical noise on your AC mains line. Try connecting to another AC circuit (not merely a different plug, but a different circuit).

•Check to see if you have any halogen lighting or dimmers on the same circuit as the preamplifier, as they can be the cause of hum in power supply transformers.

7.There is a noticeable change in volume between one input and another, even though the volume was not adjusted.

•You may need to adjust the input offset setting to compensate for differences in output level between source components. Conversely, the input offset setting may have been adjusted inappropriately. Either way, you can correct the problem by going to the following location in the menu system:

Menu ➝ system setup ➝ input ➝ input name ➝ offset where input name is the input which needs to be adjusted.

•If the input that seems incorrect is the phono input, make sure you are using the proper gain setting for the type of cartridge you are using. If in doubt, consult with your authorized Classé dealer.