15X - ProScan - USB Audio Quality & ?Interference


Premium Subscriber
Nov 15, 2018
After a Win 10 reinstall I was finally able to get a Sabrent USB Audio stick to install properly via PnP. I read both ProScan's Audio setup info and many posts here on same.

Am getting crappy audio with a low whine or hum and fast thumping clicking noise. Actual scanner traffic audio can be heard in background but at VERY low level. Am attaching a mp3 of the audio I recorded from PC's speakers (while Proscan's loopback selected) with phone.

Here's my setup and some of Proscan's settings.

1. Sabrent Audio stick is connected to a powered USB 3 hub on desktop
2. BCT15X has a 3.5mm stereo cable from the REC output connected to the stick's MIC (pink) input. Cable is new https://www.amazon.com/gp/product/B00NO73MUQ
3. Scanner connected to PC using Uniden's USB cable.
4. Audio Control, Recorder, Capture Screen: Input Device is Primary Sound Capture Device. NOTE: Level meters very LOW unless scanner volume up HIGH. Nothing shows on Signal Scope. See screenshot

recorder-capture settings.png

5. Windows Mixer:
Playback Tab= PC's Speakers (Realtek Audio, Default Device).
Recording Tab: Microphone - USB Audio Device, default.
Mic Properties: "Listen to this device" NOT checked.
Custom Tab: AGC checked. Note: I tried disabling AGC and makes no diff.
Levels: Mic is set at 86
Advanced Tab: Sample Rate/Bit Depth: 1 channel, 16 bit, 44100Hz

6. RECORDER Screen: While recording I can see via the Record Level Meter that it's tied to scanner volume.

Please ask away if more info needed.

Two issues:

1. Interference from what and how to fix?

2. How do I set a fixed record audio volume/level vs. dependent on scanner's volume?


Sep 8, 2006
Stockholm, Sweden
You are probably shortening out the audio as the mic input of the USB stick are grounded and not "floating" and isolated from ground as it needs to be. You then have to use a ground loop isolator to make it work. But are the mic input campatible with a loudspeaker output? Maybe you should use the earphone jack?

There's lots of ground loop isolators, they all work the same. Get the chepeast one.