WAV to MP3 Batch Process L-R balance shift?

I am trying to batch process a folder of stereo WAV files to MP3. I can do this with the Batch processor but the balance of the audio shifts hard left on the MP3 (there is some level on the right). If I process just one file at a time using Render, I get the correct MP3. Any advice what si happening here?

Update: As mentioned, this occurs in Batch process but I also find the error when I use the “Render” shortcut tab, even for a single WAV file. The only way I am having success creating a 1 to 1 WAV to MP3 copy is to process using the Render button in the Master section, one file at a time.
There must be a setting I have wrong. Thoughts?

Can you show a picture of the input and output files?