I am trying to use a USB / serial adapter made by prolific technology. When I plug the device into the USB port of my Macbook Pro (into the slow USB port 1.5 Mbytes) the device is mounted. I can use it into my application for only 9 to 10 seconds. It does work correctly. After 10 seconds the connection is brooken like the device was asleep. If I quit the application and re-start again it does work again for a maximum of 10 seconds. This application used on a regular PC do work well with the same device. Do anybody have an explanation ? Otherwise PW work fine Phil Macbook Pro 2 Go PW build 1812.7 2.1 Beta 6 for Mac OS X running XP guest OS with 512 Mbytes Ram and USB controller Autoconnect On.