Hello Eric,
Thank you for the lightning fast response!

Regarding Amazon Linux, it's evolved from Red Hat Enterprise Linux (RHEL)
and CentOS. While not my personal preference yet, it's required for my AWS
Lambda project. Using yum, The following packages were *not *found:

yum install ladspa ladspa-devel

Thank you for the clarification on LADSPA Path. I'll be sure to set that
when running, not worrying about it when building at this stage.

You mentioned a need to install ltdl. I was able to install the following,
also installing the libtool-ltdl dependency:

sudo yum install libtool-ltdl-devel

While unable to enable LADSPA yet when building SOX, I was able to locate
config.log, posting the full log contents here for further troubleshooting:

https://pastebin.com/XykNdexE

Thanks again for the excellent support while troubleshooting this. :)

Kind regards,

Chris