Welcome to the new FlexRadio Community! Please review the new Community Rules and other important new Community information on the Message Board.
If you are having a problem, please refer to the product documentation or check the Help Center for known solutions.
Need technical support from FlexRadio? It's as simple as Creating a HelpDesk ticket.

The way I solved random missed decodes on WSJTX / JTDX on W10

kg5zzb Member
edited June 2020 in New Ideas

Hello y'all,

I was having random no-decodes and no decodes at all on WSJTX & JTDX and

after spending several hours following many threads on this forum, I found this particular solution that worked for my setup.

I really needed to know who was the troublemaker: WSJTX, DAX or the PC

After making sure the PC and WSJTX were 100% tuned, I decided to focus on the DAX.

I started recording satisfactory decodes and no-decodes on wav files.

I analyzed each file with an audio program (Goldwave) and didn't 'see' anything strange on the waveforms...they look identical to me.

However, when I played the files on the loudspeaker I could hear short and fast 'clicks' on the files that couldn't be decoded by WSJTX.
That opened my eyes there was something wrong with the audio sample that WSJTX was listening to. 

Here is what solved it for me:

I went to the DAX AUDIO RX properties and changed the sampling rate from STEREO to MONO.

after doing this for the DAX Audio RX, voila! 100% good decodes and no more 'clicks' on the wav files recorded by WSJTX

I tested it for several hours and runs really nice with 100% satisfactory decodes!

Bonus tip

I also make sure WSJTX has the highest priority (realtime) as a process on windows 10.
Open your task manager and locate the WSJTX process and set it for real time priority.

You can read more on how w10 handles processes here.

I hope this will help those who have issues with random no-decodes on WSJTX.

Happy FT8 & DX!

I uploaded the recorded WAV files in case you want to hear them and compare them to yours.
https://gofile.io/?c=e4aozk  - No-Decode sample
https://gofile.io/?c=2bpXnN - Good Decode sample


  • George KF2T
    George KF2T Member ✭✭✭
    edited June 2020
    This suggests your PC has too few available resources, either through insufficient hardware or something in software. Changing an application priority to “real time” is not advisable. Check your system for applications and background processes that are consuming resources.
  • Sergey R5AU
    Sergey R5AU Member ✭✭
    edited March 2020
    Hi JP! I have no issue with “clicks” and drop frames in Jtdx or Wsjt, always set 24bit 48kHz stereo , however my friend RT3D once mentioned that . Results of investigation : antivirus apps Right now I not remember what is a type but he uninstalled and using other one without troubles . “Clicks” can caused by CPU overload as well. Nevertheless thank you for topic , I’ll repeat on my side.
  • John - K3MA
    John - K3MA Member ✭✭
    edited March 2020
    Thanks for the information.  I do not operate FT8/FT4 very often but I was wondering why I would see a station on the waterfall but not always get a decode.  I will give your solution a try and see if it also works for me.
  • kg5zzb
    kg5zzb Member
    edited March 2020
    Good morning George,
    Thanks for your input. 

    I learned the 'high-priority' trick from my PC gaming experience. 
    I would only do this if I wanted to maximize the performance of a game running on a PC by squeezing all the available resources.

    Every configuration is different :/
    If your PC is dedicated only to HAM radio and you are only using FT8, setting 'high priority' will **** up your entire processor, leaving no cycles for anything else than the process you set for high priority.

    You are right and it should be used with care to avoid slowing down your entire system. 
    In my case, my PC configuration allows me to do this since I have a lot of available resources to run WSJTX on real-time.

    My HAM PC:
    - Processor: Intel(R) Core(TM) i7 CPU     870 @ 2.93GHz, 2927 Mhz, 4 Core(s), 8 Logical Processor(s)
    - Installed Physical Memory (RAM) 16.0 GB
    - Video: AMD Radeon RX 560 Series 4GB RAM

    So many variables in place, ugh! :)

  • Patrick
    Patrick Member ✭✭✭
    edited March 2020
    How do you set priority  (real time selection) so that it is permanently set.  I did the change, but when the app is stoped and then restarted it goes back to normal.  
  • kg5zzb
    kg5zzb Member
    edited March 2020
    Hi Pat, I did a google search and I found a way to make it permanently

    You create a shortcut to the app with the specified command line above :)

    PS: try the set it to 'high' , or 'above normal' first.

Leave a Comment

Rich Text Editor. To edit a paragraph's style, hit tab to get to the paragraph menu. From there you will be able to pick one style. Nothing defaults to paragraph. An inline formatting menu will show up when you select text. Hit tab to get into that menu. Some elements, such as rich link embeds, images, loading indicators, and error messages may get inserted into the editor. You may navigate to these using the arrow keys inside of the editor and delete them with the delete or backspace key.