Extremely Strange Panning Issue

Hello All,
 
First, here's the current rig:
* AMD Ryzen 1700X, 16 GB RAM, SSD, Scarlett 2i4
* Windows 10 (Version 1703)
* Cakewalk Sonar Platinum (Version 23.7.0 Build 37)
* Using ASIO drivers (96000 Hz SR @ 24 bit depth)
 
Hoping that someone has either heard of this, experienced this or knows what might be causing this... The issue I'm having is independent of a specific project, track or FX/plugin. What's happening is that any time a track is hard panned (literally 100%) I get bleed over into what should be the silent channel. I reproduce this regardless of whether I use the track pan control, channel tools, or even mute a channel on the hardware output in the mix console. What makes it REALLY weird is that if I back the pan control to 96% I ALMOST get a perfect hard pan. Now, my gut instinct was that this was a hardware issue so I swapped to an older first gen 18i8 that I had; no change. I've gone through multiple iterations of isolating and identifying, and the nail in that coffin in my mind was that if I export a single track panned to 100% either direction, the exported WAV exhibits the same issue. If I export a track panned to 96% either direction, I again get an almost (but not quite) perfect hard pan. Recognizing that the audio interface was still a common factor I plugged a set of headphones into the motherboard sound card output and replayed the exported files; same exact issue. To further isolate I copied the audio files to my phone and played back from there... Same result.
 
I'm at a loss at this point. My gut is that this is likely a Sonar issue (particularly since ASIO exhibits this issue) but clearly Windows is always a layer that must be consider since it cannot be removed from the equation. While I do however feel like Windows is unlikely to be the culprit, who knows...
 
Anyone seen this? Have any ideas on what to try?
 
Note: I have verified that I wasn't doing something dumb like having offset mode engaged.
 
Thanks all! Have a great day/night where you may be!

Thanks for the input!
 
Oddly enough, at 96% panning I do show activity on the meters for both channels. At 100% only the properly panned channel shows activity (but I obviously have audio in the channel that should be silent).
 
This particular audio interface unfortunately does not have it's own control interface except for a very limited buffer control in the ASIO control panel. Honestly, something screwy with the audio interface settings is exactly what I thought was the likely culprit but I can't figure out why exported audio exhibits the same problem even when played back from a different device altogether...
 
I'll continue to poke around and mess with drivers. I'm going to do a manual uninstall of all Focusrite drivers to see if that helps. In the meantime, additional ideas/comments are very welcome!
 
Thanks again!

Do you have any stereo FX sends ? By default Stereo FX sends for FX, Exc are straight up and don't follow track panning.
Make sure to pan the send as well unless you want the stereo bleed.
 
A good way to test is to bypass the FX send.

Thank guys. I first noticed this in an older project and to remove variables I started a completely fresh project with literally nothing but two mono audio tracks in it; the problem persisted. The project was not based on a project template and therefore was completely blank with absolutely no FX/plugins/softsynths added. There are no effects loops, inserts or sends in place either.
 
At this point I'm going to open a support case with Cakewalk as I am fully convinced this is one hundred percent a Sonar issue (and a new one at that). If anyone is feeling generous I'd be curious to know if you can duplicate it.
 
Thanks all!

Use Google for searching, e.g. "SITE:forum.cakewalk.com {keywords}".
 
I'd be glad to look at your two-mono-track test project. Post it on DropBox or something.