Voice over UDP problem

For realtime audio, I don't think you are going to be able to use VB6 in one program. You are going to need to have some sort of data buffer that you can access from 2 places at once. You need 1 program to read the data from the net (maybe a com object). 1 that plays the audio. As the program/com object reads from the net it will need to communicate with the player letting it know what position it is at, so if the data comes over too slow, the player can pause.

You will need to use TCP/IP as it will guarantee the packets get there in the right order. There will be virtually no delay unless a packet gets dropped and has to be re-sent.