Troubleshooting Aspen Evolution Pro Max audio issues

[BaldEagle]

Anyone else had this problem with their Max upgrade?  Audio output from Aspen into a GMA 340 audio panel.  Audio alerts working as advertised, but there is a loud interference noise over all the headsets 100% of the time.  The issue goes away when the Aspen is running off battery or if the Aspen is powered down.  The background noise is heard over the headsets but not through the speaker when intercom selected on audio panel.  Thought I'd reach out here to see if it's a known issue before I ask the installer to start troubleshooting.  A bandaid solution for now is to reduce the volume on the headset(s) and increasing the volume on the radios, which reduces the background whine, but it's still annoying.  My guess is something is improperly shielded, but I'm a rank amateur when it comes to avionics.

[carusoam]

Let’s see if the Aspen Guy is around... @Andy Smith ( audio feedback when Aspen Max is on, feed back goes away while running off the battery)  

I’m not sure if I have accidentally added some meaning that doesn’t belong... see B. Eagle’s post for specifics...  

Best regards,

-a-

[PeytonM]

Just had mine done today; no issues. Very pleased. 

[Baker Avionics]

  On 2/26/2020 at 9:53 PM, BaldEagle said:

Anyone else had this problem with their Max upgrade?  Audio output from Aspen into a GMA 340 audio panel.  Audio alerts working as advertised, but there is a loud interference noise over all the headsets 100% of the time.  The issue goes away when the Aspen is running off battery or if the Aspen is powered down.  The background noise is heard over the headsets but not through the speaker when intercom selected on audio panel.  Thought I'd reach out here to see if it's a known issue before I ask the installer to start troubleshooting.  A bandaid solution for now is to reduce the volume on the headset(s) and increasing the volume on the radios, which reduces the background whine, but it's still annoying.  My guess is something is improperly shielded, but I'm a rank amateur when it comes to avionics.

Expand  

You are spot on Mate!!!!  That is what happens when it is not shielded correctly for the audio lines!

[tmo]

@Baker Avionics - based on the description of the workaround (turn up radio, turn headset down) is it likely that the cables between the audio panel and the headset jacks are to be looked at first?  If turning the radio up didn't change the ratio of signal to noise, I'd start with the connections between the radio and the audio panel, but it seems the noise is added "downstream" of the radio.

[Baker Avionics]

  On 3/4/2020 at 10:47 AM, tmo said:

@Baker Avionics - based on the description of the workaround (turn up radio, turn headset down) is it likely that the cables between the audio panel and the headset jacks are to be looked at first?  If turning the radio up didn't change the ratio of signal to noise, I'd start with the connections between the radio and the audio panel, but it seems the noise is added "downstream" of the radio.

Expand  

My "Spot on" was more about the shielding issue, not the workaround.  I appreciate the clarification @tmo I don't want anyone to think it is a good thing to keep doing.  The main thing is to ensure the shielding is correctly done and grounded away from a power ground. Further, my question would be does it do the same with the engine running as if just on Battery power?  If only when running, is it the same on both mags?  One last thing, what audio panel and intercom does he have and does it include an entertainment/music jack?  I guess I should include @BaldEagle too!  LOL.  Those are the questions I would ask for the following reasons:

With engines running and not on battery only- Shield at P-lead may be broken or a cust wire running from the engine compartment to the cockpit causing issues.

If only when engines running, run on individual mags to see which one or both.

Entertainment/Music Jack- If the ring is touching ground, it can cause weird issues like this.  Be sure the jack is completely isolated from ground. 

 

That's where I would go IF the shielding on the Aspen is not the issue.  

[tmo]

Thank you, kind sir, for the detailed explanation.

[BaldEagle]

Thanks @Baker Avionics @tmo  I'm trying to schedule getting this back into the shop to resolve.  The noise persists whether the engine is running or not; no broken P leads.  Audio panel is a GMA 340 / no music jack.  The noise from the Aspen goes away if it's running on battery or is powered down.  What is interesting is, with the Aspen powered up and not on battery, if I select "speaker" on the audio panel I don't get the background noise through the speaker, but I do get it though the headsets on pilot and co-pilot side (I haven't tested the rear seat jacks).

[Baker Avionics]

  On 3/5/2020 at 10:46 PM, BaldEagle said:

Thanks @Baker Avionics @tmo  I'm trying to schedule getting this back into the shop to resolve.  The noise persists whether the engine is running or not; no broken P leads.  Audio panel is a GMA 340 / no music jack.  The noise from the Aspen goes away if it's running on battery or is powered down.  What is interesting is, with the Aspen powered up and not on battery, if I select "speaker" on the audio panel I don't get the background noise through the speaker, but I do get it though the headsets on pilot and co-pilot side (I haven't tested the rear seat jacks).

Expand  

Ok, cool, great info!  Now, what if you are in ISO mode?  What about trying one jack at a time and and/or both at the same time?  Does it matter?  Now all of this is assuming that WHEN the shielding is checked, it will be good, though I think it will show its ugly face then.  Ground issues are the worst and wreak havoc on Audio Systems.  

[Baker Avionics]

  On 3/5/2020 at 10:46 PM, BaldEagle said:

Thanks @Baker Avionics @tmo  I'm trying to schedule getting this back into the shop to resolve.  The noise persists whether the engine is running or not; no broken P leads.  Audio panel is a GMA 340 / no music jack.  The noise from the Aspen goes away if it's running on battery or is powered down.  What is interesting is, with the Aspen powered up and not on battery, if I select "speaker" on the audio panel I don't get the background noise through the speaker, but I do get it though the headsets on pilot and co-pilot side (I haven't tested the rear seat jacks).

Expand  

You can always come up to Grants Pass- 3S8. We love visitors!!!

[carusoam]

San Diego to southern Oregon....

a mere day trip in a Mooney!   

-a-

[BaldEagle]

  On 3/5/2020 at 10:57 PM, Baker Avionics said:

You can always come up to Grants Pass- 3S8. We love visitors!!!

Expand  

Taking the Mooney up to the San Juan Islands via Southern Oregon this summer (likely stop over in Ashland).  Hoping to get it fixed well before then however...

Thanks for all the helpful feedback.

[BaldEagle]

Update: Max getting replaced under warranty.  The bad news is that I won't be seeing a replacement until Aspen's reboot issue is resolved.  No ETA on that currently.  The installer did confirm that my soon-to-be-replaced unit is unaffected by the reboot issue so at least that's something while I wait for the replacement.

[LOCOLJ]

I thought I would bring this up again, because I am having some audio noise following the upgrade to the max.  As soon as the unit powers up, I am getting a quite loud audio hum when the plane is running.  Is this similar to what you saw? and did a new unit resolve the problem?  To my knowledge, they followed the install spec when the additional wire was connected to the audio panel.   

[BaldEagle]

  On 10/8/2020 at 2:36 PM, LOCOLJ said:

I thought I would bring this up again, because I am having some audio noise following the upgrade to the max.  As soon as the unit powers up, I am getting a quite loud audio hum when the plane is running.  Is this similar to what you saw? and did a new unit resolve the problem?  To my knowledge, they followed the install spec when the additional wire was connected to the audio panel.   

Expand  

I haven’t replaced the unit yet, I’ll chase that up once I’m done with the annual.  Something you can try: disable auto brightness (when booted hit Menu, then press left knob and twist left or right) and try adjusting the display brightness manually.  If I set it to its very lowest or highest setting the noise goes away.  I can live with this until I get the unit returned, but it would be annoying if I flew at night.

[LOCOLJ]

Thanks for the info.  What you indicate improves the problem, makes sense in my case.  I did notice that the noise changes especially when my hand was on in front of the unit.  Is this a known issue with Aspen? Did they push back when you discussed sending it back?

 

[Baker Avionics]

  On 10/9/2020 at 2:07 PM, LOCOLJ said:

Thanks for the info.  What you indicate improves the problem, makes sense in my case.  I did notice that the noise changes especially when my hand was on in front of the unit.  Is this a known issue with Aspen? Did they push back when you discussed sending it back?

 

Expand  

Can you send or post a pic of the wiring harness that is hooked to the Aspen?  There is a reason and that is there should be a ground wire from the connector to the instrument panel and there should be about 12" of over braid on the entire Aspen harness from the connector towards the front of the plane. If that makes sense

[LOCOLJ]

Thanks for responding, I will try to get a picture over the weekend.  I know the large braided shielding over the harness is in place, I will look for the ground to the instrument panel.  Additionally, the installer grounded the  shield  of the wire that goes to the audio panel at the aspen per the wire diagram outlined by Aspen. 

[LOCOLJ]

BaldEagle, your description regarding the brightness reduces the noise, thanks for the information.  Included is a pick of the unit.

[Cessna Guy]

I’m having the problem as well. I did not have it with just the Pro Max PFD but when the MFD got installed it started. It happens on battery with the engine off and when engine is running. The only way I can get the noise to stop is to depress the Pilot Isolation button on the 340 audio panel. The sound is an electronic hum / Morse code sounding noise, extremely annoying.  Has anyone successfully resolved the problem?  Please advise. 

[carusoam]

Let’s see... this can be tough...   but here goes....

 

Welcome aboard, Brand Ce guy!

Down deep were all airmen, and some day we are all going to need some help....

Best regards,

-a-

[Cessna Guy]

  On 11/22/2020 at 7:27 PM, Cessna Guy said:

I’m having the problem as well. I did not have it with just the Pro Max PFD but when the MFD got installed it started. It happens on battery with the engine off and when engine is running. The only way I can get the noise to stop is to depress the Pilot Isolation button on the 340 audio panel. The sound is an electronic hum / Morse code sounding noise, extremely annoying.  Has anyone successfully resolved the problem?  Please advise. 

Expand  

 

  On 11/22/2020 at 8:00 PM, carusoam said:

Let’s see... this can be tough...   but here goes....

 

Welcome aboard, Brand Ce guy!

Down deep were all airmen, and some day we are all going to need some help....

Best regards,

-a-

Expand  

Thanks, airframes aside, we all deal with the same avionics challenges and this group does a wonderful job sharing insights. Thanks for including me. 

[BaldEagle]

Resurrecting this thread as I resolved the issue with the Aspen PFD background noise by replacing the GMA 340 audio panel for a PS Engineering PMA450B.  Technically it’s not resolved I suppose, but I think the PS Engineering unit constantly samples the incoming audio and is filtering the noise out.