After 10 years, the headset amplifier became a daily necessity so a long awaited enclosure was fabricated.  The enclosure was the 1st attempt at large scale thin walled printing, .5mm walls to be exact.  It didn't look very good, but it was cheap for its size.  .5mm seems sufficient, as long as their are reinforcing ribs.

4 hours of soldering yielded 2 pots & 2 switches.  It takes 30 minutes to solder a single component.  There is a place to have a line out, but it would involve 1 hour to solder 2 RCA connectors & a line input on the amplifier is a long way off.  

The headset amplifier has made some progress but has a long way to go.  The phone volume has always really been a master volume.  For some reason, the phone gain was put into the output of a summing amplifier for the microphone & phone.  It might have been assumed that the phone would always be loud enough & lions wanted a master volume.  Experience showed the phone isn't loud enough & it's a pain to adjust both the microphone & master to get the right level for either input.

A few more hours of soldering should give independent volume controls with no master volume.  

The pots are 2 channels even though only 1 channel is used.  They are the only 100k pots in the apartment & they were bought back when it just involved running down to a Radio Shack.  Getting a 100k pot today would involve a 2 week delay & shipping costs.

The debate continues of whether it's worth having a physical amplifier or using the confuser's sound card for conference calls.  The physical amplifier can be used for any call on a phone & any call on a confuser.  The confuser sound card would only be useful for those calls.  The confuser really needs presets for conference calls & videos.