FM radio gain control cuts out the left channel

Bug Description

Adjusting the gain in the fm radio cuts out the left channel.

Steps to Reproduce

  1. Goto sample recorder
  2. select fm radio, tune in a channel and activate monitoring
  3. Turn up the gain control, above zero the left channel cuts out with a click.
  4. As a side note, line in is set to stereo just in case that matters.

Occurrence / Frequency

Always

Found in Firmware

  • Version: 1.9.1

Attachments

None

Hi @Patrick, it’s been a while, nice to see you again :wave:

I’ve just tested this on my device but can’t reproduce. Here are the steps i took:

  • Go to sample recorder
  • Chose Radio as input
  • Enabled monitoring
  • Turned up gain to 100 (maximum)

Everything sound normal to me. Made sure my line in is set to stereo as well.
Even went ahead and turned the master volume to full gain - yes this can affect the output overall there as well. Careful if you want to test this, it gets loud.

But non of the channels cut out.
Does this happen on a brand new project as well?

For your information i’m running Firmware 1.9.1, Build 1138.

I will test further this evening and report back.
Firmware as stated 1.9.1 (latest non beta)
Just for interest, you tested it on pt tracker not tracker+

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Correct, this was tested on my rusty but trusty OG Tracker.

Left channel goes muted as soon as you turn the gain above 0 with a click. Line in was plugged in and set to stereo but radio was selected. I investigate further this evening. Ty for trying to replicate

Ah that is important information - so you have something running into the line in as well at the same time? Is it just plugged in, or also running some audio into the device?

Not running only set up to patchbay. No signal is going in.

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Good to know. i’ll give that a try. Have a patchbay so i can replicate this pretty accurately

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So, back in the studio to test it again. I have now nothing plugged in the line in. Same bug as described before. Another observation, when i set line in to mono, both channels are cut out. Short smartphone video attached.

Hey @Patrick , thx for the video. That doesn’t look good.

I tried what you suggested by plugging something into my line-in from my patchbay. But that didn’t make any difference either. Let me know if you’d like to see a small video as well just for comparison.

  • Does it happen also when you are tuned into a station or only on the whitenoise?
  • Do you still have a previous firmware (for example 1.8) for testing?

(if you don’t, i have an archive of older tracker firmwares here)

If the behaviour is the same on 1.8, it would seem more likely for it to be a hardware issue than a software one.

Let me know how that goes :crossed_fingers:

Radio is working, line in is working and so does the rest of the tracker. If its hardware, its a revision defect. Latest model sept 23 guessing mk4.
The SOC and its ic do work or not.

I will flash earlier revs.

Ok thanks for the info.

If the issue persists on 1.8, then it’s most likely a hardware defect and then it’s best if you get in touch with Polyends customer support directly or the retailer you bought the device from, for a repair. :people_hugging:

if something is unclear, feel free to message me directly as i just noticed you speak german as well - if that will help you :heart:

So now on 1.4.0 and the behaviour is different.
I reset config and here it does this:

Line in set to left as in the previous test.
Left channel is cut out as when set to stereo but right channel goes up in volume.

Sandroid, i know a thing or two. This is no normal “hardware defect” different behaviour in different firmware versions :wink:

Well going back to 1.4 is a pretty big jump, that’s why i asked you if you had 1.8, since that would be a better comparison. :blush:

Also if this was a general software issue, we would have seen reports about this already as people tend to like the radio feature.

So that leaves us with two options: Sofware + Hardware Combo or just Hardware, agreed?

To exclude any possibilities of it being configuration related, you could delete the following file from the root of tracker sd card (so it can be recreated automatically): /trackerConfig

So if you can, please test the behaviour after:

  • Flashing 1.8 Firmware
  • Deleting the config so it can be initialized clean
  • Then test the radio

If the issue still persists - it is one of the two issues mentioned above and a repair or a send-in for further analyzing would be beneficial.

I hope we can agree on this, since we both know a thing or two? :blush:

Ok, so done with flashing and resets.
So unless you want me to open this sucker the unit goes back.
Perhaps you are right and its a single faulty trace to the opamp. Whatever, it is a factory defect, no chance it blows up a single trace or ic channel afterwards.

So feel free to close the thread unless everyone else who’s reading this wants to test the tracker og and chime in.

Oh and please pm who’s interested to take the unit.
Cheers

I’m not sure if you misunderstood me?

That’s exactly what i was saying. This is most likely a defective unit.

If you get in touch with Polyends customer support directly or the retailer you bought the device from, i’m sure you can arrange a repair or exchange.

I’ll mark this as resolved as it is not a software issue, but i do hope you can get it fixed.
If you still require any help - feel free to contact me directly, start a new topic or add a comment in here. As it will set an automatic timer that this issue will close in two weeks.

Best of luck! :heart:

This topic was automatically closed after 13 days. New replies are no longer allowed.

Hey @paul-8189, you seem to have encountered the same issue. Could you do me a favor and post a video of the behaviour as well?

I’m also going to ask you and @Patrick, if you could share with us the initial part of your Serialnumber (found on the back of the device). I’m interested in the letters part of the serial (PTC... without the numbers).

I’m wondering if this is a hardware revision specific issue.

@Patrick did you go through customer support?