Bizarre recording error

Hey there learned Reaper folks,

I've run into a really odd issue that I do not think is solvable... I use Reaper to manage podcast recordings, using a Behringer UMC404HD USB interface. I've never had any problems in the past (that weren't attributable to human error) until our recent recording.

I get Reaper to render the tracks as we go as .wav files. However, in our last 30-min take, the latter 10-15 minutes of each of the four mic feeds is bizarrely garbled. This isn't a file issue, either - it suddenly kicks in around halfway through each file.

The interface itself has no ability to change sample rate, etc, on the fly, so it must have been some issue in the software. When I chop up the tracks and apply a roughly 1/3 playback rate on it, it sounds to be about the right speed, but incredibly choppy and garbled.

I imagine the recording is unsalvageable but thought I would ask here. I can provide more details as we go but just wanted a sense check to start here.