As mentioned in my other post, I have linked 2 PC''s using DirectPlay (DX7.0) so that 2 players can share the same VR environment. This all works fine over all the session types available (IPX, TCP & Modem). I have also coded full duplex audio (based on one of the examples that comes with DX7) using circular buffers) Basically, I sample the voice from the microphone input at 8K/8Bit/Mono and every 512 bytes a notify event occurs. At this point I send a network packet with this data to the other PC (Actually, I only send 256 bytes - every other sample). Once this packet is received on the other machine I take this data and stick it into the circular play buffer. This all seems to work fine over a LAN link (ie. there is enough bandwidth to cope with this info as well as the player data). However, over an ISDN 64K link, it runs like a dog! Even though it runs fine over LAN, I get echo''s of the sampled speech which get quiter. Not sure what''s going on here. Is there any other way I can compress the voice data before sending it to the other machine? Or any other method I should use? I''ve looked around for info on this for a couple of days, but haven''t really found much. I need to have this app working over an ISDN link between 2 PC''s with voice, but am having grave bandwidth problems! I don''t know much about compression, bandwidth problems, etc. This was a first pass to see if it would work. Any help on this would be most appreciated. Cheers, Taz. --------------------------------- Tarique Naseem Technical Director Maelstrom Virtual Productions Ltd. http://www.maelstrom.com