D-STAR GMSK Modem with Flex-3000 issues

Jim - K6JM

I'm planning to use a GMKS Modem with my Flex-3000 so I can transmit and receive D-STAR digital voice on HF (in conjunction with GMSKClient and a DV Dongle). With most analog radios, we connect the modem to a 9600 baud packet data connector, because it's important that we get RX audio directly from the discriminator, and send TX audio directly to the modulator, without any filtering or audio processing. I can see it will be easy to build a cable to connect the modem to the FlexWire connector and the PTT connector. I can probably configure PowerSDR to use audio input and output from the FlexWire interface, and set audio levels with the PowerSDR Mixer. I assume I'll need to turn off Compression and Equalization, though I read COMP may be needed to get sufficient audio. We'll see. Is that it? GMSK audio uses very low audio frequencies, hence the need not to have any filtering in the path. Will I need to make any other configuration changes to make this work?