Intercom Problem?

[jdfrey1]

My plane just started having an interesting problem and I was wondering if someone could help me troubleshoot the issue. The problem is with the headset audio in my plane.

I have a Garmin GMA-340 audio panel with 2 sets of jacks in the front and 2 in the rear. My family and I went flying this week and my wife who sits in the back with my son couldn't hear me through the headset. We of course troubleshot the headset and made sure it was plugged in properly and even tried another headset with the same results. Interesting thing was that she could hear other radio traffic and she could hear me when I keyed the mic. I could hear her fine so her mic was working fine. I checked the Pilot isolation buttons on my audio panel and also checked the volume and squelch knobs with the same results. The other jack in the back had the same issue. My daughter sits up front and I believe that she could hear me just fine. Does anyone have any recommendations or ideas of what the problem could be?

Thanks!

 

[skyflyer8]

My plane just started having an interesting problem and I was wondering if someone could help me troubleshoot the issue. The problem is with the headset audio in my plane.

I have a Garmin GMA-340 audio panel with 2 sets of jacks in the front and 2 in the rear. My family and I went flying this week and my wife who sits in the back with my son couldn't hear me through the headset. We of course troubleshot the headset and made sure it was plugged in properly and even tried another headset with the same results. Interesting thing was that she could hear other radio traffic and she could hear me when I keyed the mic. I could hear her fine so her mic was working fine. I checked the Pilot isolation buttons on my audio panel and also checked the volume and squelch knobs with the same results. The other jack in the back had the same issue. My daughter sits up front and I believe that she could hear me just fine. Does anyone have any recommendations or ideas of what the problem could be?

Thanks!

Here is the only thing I can think of. I know that when I adjust the volume knob on my side (copilot's) it will adjust only the volume of our voices, not the volume of the radio, unless I am mistaken. In other words, I set the intercom volume to something comfortable for my voice and my student's voice coming through the headset, then I independently set the radio volume to match, using the volume on the radio.

The GMA 340 has four knobs total, a "nested" pair on each side (left & right). Adjusting the left inner (skinny) knob adjusts the pilot's volume, and on the right side, the inner knob adjusts copilot's volume.

What some people aren't aware of is that you have to pull the right side inner (skinny) knob out and turn it to adjust the intercom volume for the back passengers. I didn't even realize this myself until I had back seaters saying their headsets were unbearably loud and I couldn't figure out what to do at first. But then I got it.

You didn't specifically state that you checked all three volumes (pilot, copilot, & back pax), so I thought I'd mention this. It could be that you somehow had the radio volume set fine to where the back pax could hear it, but not the intercom volume itself. Did you try adjusting the back seat passengers' volume by pulling out the copilot side inner knob and turning it?

If you did, then I have no idea what the problem might be.

 

[RMCN172RG]

There are two isolations on the 340 PILOT, CREW and NONE.

However none work as you described which is unable to here you on the intercom but could hear the radio calls?

 

[bjohnson]

I had a similar problem with my audio panel this past weekend. I found that the audio panel was not seated well. Have you tried giving yours a little push back into place?

 

[Jack Cunniff]

Just as an FYI - I had the same problem with my GMA 340 this past weekend.

I could hear ATC just fine, and could hear myself when I was transmitting to ATC, but I couldn't hear my right-seater, nor myself via the intercom. He could hear me via intercom and when I keyed the mic.

I used a 3/32nd allen key to loosen GMA 340, pulled and re-seated it a couple times, figuring it would clear some oxidation on the pins, and that resolved the issue.

Afterward, I could hear the right-seater just fine, as well as myself via intercom.

Thought that although this was an eight year-old thread, I found it while looking for support info, and wanted to share that in my case, pulling and re-inserting the GMA 340 resolved the issue.

-Jack