I tried to use Skype for the first time in years. I downloaded the latest but it ran silently - at least I couldn't hear what the recorded messages I called said; at the point in the call to echo123 in which it would play what I recorded I heard nothing.

I read the Skype community forum and found that I seemed to need pulseaudio, which I had to build - as well as speexdsp, speex, and json-c. It still didn't work. Some in the Skype forum didn't get it to work even with pulseaudio.

Can anyone recommend an alternative? I'm using Google Voice now but still want something else.

I assume the main reason for using Skype was for compatibility reasons with people you'd like to connect with? Just a thought - Rather than using the Skype app, maybe Skype for Web will suit you (using only your browser). It's still in beta, but may be available to you. Check here

http://blogs.skype.com/2014/11/14/pl...-for-web-beta/

As long as your sound already works from your browser, then it should work ok too.

https://www.mozilla.org/en-US/firefox/hello/

https://jitsi.org/

Probably viber?

Jitsi?
jdk

I suggest you to take a look on Tox: https://tox.chat/
It's absolutely free and decentralized (like DHT) analogue of Skype. There are plenty of clients based on it and maybe the most popular is uTox: http://utox.org/

Slack users are in a spot between fully supported and no support.

I'd think that almost any program will require you to dig into the build process on slackware.

Some help here maybe. http://slackbuilds.org/result/?search=voip&sv=14.1

I'd treat all these as a fully unsecure line and subject to interception.