Kenwood TS-570D, SignaLink USB, VarAC - !!working!! (yeah!)
Posting this here in hopes that it helps someone else solve a similar problem.
My issue was: On a setup that was very well established for JT8, JS8, PSK31, etc, I was able to get everything working enough to be able to send out beacons and CQ's (only), but could not get any RF output once a connection was established. I went down many rabbit-holes trying to figure it out, but in the end it was very, very simple....the short answer is: go to Windows Sound Control Panel, select the device that is your Signalink OUTPUT (on my machine it was "5-USB AUDIO CODEC" on the PLAYBACK tab, right click on that device >> click Properties >> click the ADVANCED tab >> change the setting to "16-bit, 44100 Hz (CD-Quality)" >> OK >> OK
Once I did the above, setting the sound output format to 44100 Hz on the SIGNALINK OUTPUT, I was able to transmit and make QSOs just fine. I hope this helps someone!
73 de KG9NI
To get to Sound Control Panel on Windows 10:
Press Windows + R keys together to launch the Run dialog box.
Type mmsys.cpl and press Enter
An important update to this post - as it turns out, the sound output format change was a red herring - that is not the solution. The solution that provided flawless ongoing operation with my station was to revoke exclusive control of the soundcard device - see the attached image for the setting that I unchecked within Windows Sound Control Panel for my SignaLink USB output. I hope this helps someone!
Station is: Kenwood TS-570D, Signalink USB, HRD 6.8.0.372, VSPE 1.3.6.970, VarAC 8.2.0, Windows 10 Pro.
I have PTT configured via VOX with no problems. Frequency control is via CAT with Kenwood Generic, connected to a virtual serial port created within VSPE. See my other post regarding this: https://www.varac-hamradio.com/forum/varac-hf-discussion-forum/hrd-varac-vspe-rig-control-logging-ts-570d-signalink