[AEP to MP4] Results in 2 Files: MP4 and M4V

[AstroBoyd]

I'm having issues exporting my After Effects file to an MP4 File. I'm using a modified version of the "YouTube 2160p 4K" preset. Everything was pretty much left the way it was except where I checked the "Use Maximum Render Quality" checkbox and changed the audio sample rate down to "44100 Hz". Previous files exported correctly as one MP4 file with this method, but this one seems to act strange. It renders an MP4 file that's just the audio of the project, and a corrupt M4V file that has numbers after the project name. For Example: OBS003.aep = OBS003.mp4 and OBSOO3.10988.303321.m4v. I've rendered it numerous times and each time, the corrupt file's name is always different and varies in size. I've tried to purge the cache in AE/AME and reset the computer--but I still get the same end result. I've tried to recreate the AE Project from scratch and ended up with the same result. I've also tried saving the output file on external drives but end up with the same result. The log file shows that the project outputted successfully as well:

08/12/2018 04:07:05 PM : Queue Started

- Source File: Q:\[Album Artwork]\OBSCVRA\Episode 003\OBSOO3.aep

- Output File: C:\Users\KNEO\Desktop\YouTube\OBSOO3.mp4

- Preset Used: Custom

- Video: 3840x2160 (1.0), 23.976 fps, Progressive, Hardware Encoding, 00:52:35:00

- Audio: AAC, 320 kbps, 44 kHz, Stereo

- Bitrate: VBR, 1 pass, Target 40.00 Mbps

- Encoding Time: 02:36:36

08/12/2018 06:43:42 PM : File Successfully Encoded

08/12/2018 06:43:42 PM : Queue Stopped

The source files used within the AEP are an AIFF audio file, and 10 JPG files.

[AstroBoyd · Accepted solution]

**Update**

I think I've found the issue. It seems to do this when the renderer is set to "Mercury Playback Engine GPU Acceleration (CUDA)". I have the latest Nvidia drivers (v398.82). My card is a GTX 1050. If I set the renderer to "Software Only", it renders a proper file.