I have created Albert's FT232 IR-tranceiver using UM232R evaluation board. I do not need receiver option, so only boosted transmitter part is currently implemented and used. I want to use this blaster with my HTPC to control TV, AV receiver etc. During my work I have tested my blaster on 4 different hardware platforms (2 laptops, my PC and HTPC) and it seems, that correct transmitting of signals is only available on platforms equipped with Intel's UHCI USB chipsets. While connected to my PC or Intel-based laptop transmitter works fine and is able to control my TV, AV-receiver and even old JVC mini system with "stock" remote configuration files. But when I connect blaster to HTPC (Ion based) or to old Laptop (Nec USB chip) with OHCI USB controller, I am unable to control my equipment. I have checked IR transmission with CCD camera -- everything is fine. I use the same linux kernel on all devices, same set of config files, ftdi libraries and same sources. Unfortunately I have no oscilloscope to debug problem on the HW layer, so I need your advice, how to start to workaround this problem.