Everything was fine last night at about 9pm. I shut the entire system down with no issues.

First thing this morning booted up and loaded BIAB and Chrome browser. No issues with bootup. Initially BIAB worked visually (cursor would move bar-to-bar) but no audio. YouTube audio works fine.

I'm running W10 on a ThinkPad laptop with an M-Audio Fast Track C400 via USB (oldie but very quiet interface). Most of the files I use are Realtracks.

Looked at BIAB audio settings, they all look fine (WAS driver, "Audio Driver" points to the M-Audio in and out, "Output Always On" box checked, "Use Default Device" box checked. "Exclusive Mode" box not checked. Latency says 30ms, but since I just use BIAB for backing tracks I've never cared. Looked at Windows Settings, Devices, Audio. The C400 shows up active. I've pointed the drum and realtracks to the external drive and all the mixer track selections are in green, showing they're connected correctly.

Right clicking on desktop lower-right speaker icon pulls up windows volume mixer where I see the M-Audio Device, the System Sounds icon and the BIAB icons, all with their volume controls max'd and nothing muted.

When I left click on the lower-right windows speaker icon it shows the M-Audio is active. I can click on that again and see the laptop speakers option. I can select that and the audio (from YouTube) goes to the laptop speakers, no problem. When I go back and select the M-Audio the YouTube audio goes there, no problem -- except BIAB still not working. I tried running Cakewalk/Sonar, that works fine.

I did BIAB "Return to Factory Settings", still would not work even with the default preferences. It seems interesting that after I've done that BIAB loads fine but now nothing at all happens when I hit Play or Generate and Play. All the BIAB icon buttons react visually to mouse clicks. When I click on "Pianos" in the mixer and click on a piano key I see the key visually react to the mouse click, but still no audio.

I run the Audiophile version with the BIAB (64 bit) app running from the laptop's SSD and the Realtracks etc. from the external drive PG sent (Option 2), so I reloaded BIAB. Note that I did not delete or uninstall anything before I did this. No change. Tried right clicking on the BIAB desktop icon and "Run as an Administrator" to be sure that wasn't the problem. No change.

It now occurs to me to perhaps try reloading BIAB and use the option that runs the BIAB app itself from the disk PG sent me might be a next troubleshooting step?