Any suggestions for simple voice chat solution for a PHP based website. We already have a text chat in place, client now wants voice chat too.
Voice chat simply isn't going to happen with PHP. Such a thing requires a dedicated chat server/service; your client may be interested in something like Skype for Business or Google Talk. Both of these things (as I recall) will require an out-of-browser product to be installed.
You could problably use Adobe flash.
PHP can solve a lot of problems but not anything like voice chat.