sftp and scp stall on large file uploads

I have an Orbi system and I noticed that trying to upload a large file, 1GB+ (using terminal in MacOS) with either SFTP or SCP to an online location (AWS EC2 in this case) the upload will stall and fail with a broken pipe error. However, if I plug directly into the modem (ATT) the file upload works flawlessly.  The exact error:

-packet_write_wait: Connection to x.x.x.x port 22: Broken pipe lost connection

I know it's not a procedure or permission issue, and as I mentioned going straight through the modem works, but when connected to the Orbi (wired or wireless) it fails.  Ideas?