Well, well, well. I have worked with the 1 sec. delay (8000 byte packets) with my devices for a while. Not that I like it but... it works with Nexus Phones and tablets, Motorola, LG, Alcatel phones, HP tablets, Acer, and so on with same results. A few weeks ago I got a Samsung S7 phone. With that phone the serial transmission is SLOW, SLOW, SLOW using the same program and parameters. Any idea what is goimg on with this USB Libraries?