Troubleshooting MC-66 and MCA-66

Written by
HTD Staff
April 12, 2024 at 6:09:00 PM PDT April 12, 2024 at 6:09:00 PM PDTth, April 12, 2024 at 6:09:00 PM PDT

Here are the most common issues we hear about from customers using one of our whole-house audio systems built around the MC-66 or MCA-66, along with suggestions to resolve them.

Issues Related to the HTD Home Audio App

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Issues Related to a KC6 or KC7 Keypad

Keypads are only recognized by the system when the central controller (model MC-66 or MCA-66) is first powered on. If you connect a device while the system is already powered on, that device will not be recognized and will not work. Power cycle your system to give the MC-66 or MCA-66 the opportunity to identify the keypad:

Best steps to power cycle your system:

  1. 1. Make sure amplifiers are in sleep mode or powered off
  2. 2. Power off the MC-66 or MCA-66 using the power button on the front.
  3. 3. Wait 10 seconds. Press the power button back in AND WAIT 15 SECONDS FOR THE SYSTEM TO FULLY BOOT UP.
  4. 4. Power back on the amplifier(s) if powered off.

If the keypad was previously working properly, but it suddenly is not, power-cycling the system using the steps above will likely resolve the issue. That said, it is best to check the following that could have caused the issue in the first place:

  • Are you using a patch panel for your Cat 5 (or higher) cable? It is always best to avoid patch panels with a whole-house audio system. See "MISTAKES to avoid when preparing your home for a whole-house audio system?"
  • Check that both ends of your Cat cable followed the same 568A or 568B standard and that ALL 8 conductors are properly terminated. It is NOT okay to simply use your own sequence at both ends because the 8 conductors are more accurately defined as 4 twisted pairs. The "twisting" makes a difference - you must follow 568A or 568B. And, unlike ethernet which only makes use of 4 of the 8 conductors, HTD whole-house audio systems utilize all 8. See page 17 (Addendum) of the Owner's Manual for details.

Some other problem? Determine if the issue is with a keypad or a zone on the central controller:

  • Try connecting the keypad at the central location using a short, factory-terminated Cat 5 or higher cable. Be sure to restart the central controller before testing.
  • Try connecting a different keypad. Be sure to restart the central controller before testing.
  • Contact HTD

Issues Related to Volume

Volume control on the MC-66 or MCA-66 ranges from mute (0) to a maximum of 60. With the app and the KC7 keypad, these numbers are clearly displayed; with the KC6, a series of 7 LEDs indicate the approximate position of volume across this same range of 60. 60 discreet volume levels provides a fine level of detail for controlling volume.

For most listeners, everyday listening will typically have volume set in the 15-30 range. Loud parties, or outdoor spaces, may require a higher volume setting, but you should almost never need the system to get above 50.

If you are having to set zones to these higher volume numbers just to obtain everyday listening levels, then chances are good your system is not optimally set up. It is important to understand that the audio source will output a volume signal level, but only the amplifier creates volume. All other "volume controls" are simply attenuating (reducing) this level.

To troubleshoot, start with the source:

  • Traditional audio sources such as a DVD player provide a strong, fixed level audio output signal that is not likely to require any adjustment.
  • If you are using a smart phone or tablet as your source, you are likely using what is really a "headphone level" output. This signal level is slightly lower than a traditional source output when its volume level is at maximum. That said, a smart phone can be a great source, but don't reduce the signal further by lowering the volume on the phone or tablet itself; instead, keep it at maximum and control the volume level from the HTD Home Audio app or a keypad.
  • Some music streamers include a fixed audio output level and others allow it to be variable. When you set up your streamer for the first time (using their app), fixed volume is preferred. If unavailable, set the output volume level to maximum.

Next, consider the app used for the streaming service such as Spotify, Apple Music, Pandora, etc. Streaming service apps are primarily used to select the artist, song, or playlist you'd like to hear. If the app offers a fixed volume setting, use it. If not, set and keep the volume level at maximum.

Finally, check the level knobs on the front of your 12-channel amplifier(s). In most cases, these should also be turned all the way clockwise in order to get the most out of your amplifier's power. Adjust these level knobs counter-clockwise only when you want to limit or cap the volume for a particular zone (e.g. kids rooms or outdoor areas).

If most of your sources are performing as expected, but by comparison one has low volume, then you may simply be using a source with a low level output. We offer line gain-boosters that fix this. Read more.

If you are only experiencing a low volume issue in one zone and the level knobs on the front of the 12-channel amplifier for the speakers in that zone are turned all the way up, you may have a problem with your speaker wiring. When speakers are wired "out of phase" with one another, their sound waves can cancel each other out. This effect is most obvious with lower frequencies where sound waves are larger. The result is audio that sounds thin or weak.

A convenient way to check for this is to disconnect just one speaker at the amplifier. If you have two speakers in a zone and the sound improves when one or the other is disconnected, then they are wired out of phase. An easy fix is to swap the red and black wires on JUST ONE OF THE SPEAKERS. This will correct for any mis-wiring that may have occurred at either the amplifier or at one of the speaker terminals.

I’m not hearing anything out of one or more of my zones.

  • As with volume issues described above, start with the source. Make sure it is outputting a strong signal and that you have the correct source number selected for the zone. If you are certain the source is outputting a signal, try replacing the cable that connects the source into your MC-66 or MCA-66 controller.
  • On the front of the controller, confirm you see a blue light next to the zone number you are testing. Only zones that are currently powered on will display a blue light.
  • If you have an MC-66 and are not getting sound in any of your zones, confirm the amplifier is powered on and not in sleep mode. With older HTD models, the main power indicator light will display bright blue when the amplifier is on and active, and a dimmer blue when the amplifier is in standby. Current model 12-channel amplifiers will be bright blue when active and amber when in standby. Look for a 3-position switch on the back of your amplifier that is labeled “On Auto On Trigger”. Review pages 9-11 of the Owner’s Manual to confirm your MC-66 and amplifier(s) are connected and set up correctly.
  • Confirm the “1 2 Line” switch for your amplifier channels are set correctly. Unless you are using more than two amplifier channels for the zone in question, then the left and right variable outputs for that zone will likely be connected to “line inputs” on your amplifier channels. In this case, the switch should be set to “Line”.
  • On the front of your amplifier(s), confirm the level knobs for the amplifier channels used to power the speakers in the zone are set between the 3:00 and the maximum 6:00 position.

In one of my zones, I only hear half of the speakers in that room.

You most likely have a bad RCA patch cable connecting the zone on your MC-66 to the amplifier channels used for that zone. Replace it with a known good cable.

With one of my sources, I only hear half of the speakers in every zone.

You most likely have a bad cable connecting the source into your MC-66 or MCA-66 system. Replace it with a known good cable.


Not seeing your issue or are unable to resolve your issue? Please contact us and we will do our best to help.