Thanks for the tip, I tried removing the UnitControl stuff from my Startup-Sequence and guess what - the settings were still the same. The same ones that I have set in the bootmenu even.
@patrik
Most likely this is because UnitControl writes the settings to the RDB instead of enabling them on each boot as the CSPPC pre-boot menu does. You don't need to call UnitControl from startup. You probably never did. If your drives were falling back to asynchronous mode, it was happening because your termination wasn't set up correctly.
@Framiga
If the CSPPC pre-boot menu, and UnitControl do EXACTLY the same thing, why do the CSPPC pre-boot sliders allow less than half the range that UnitControl allows, and only half the transfer speed after setting up a drive with UnitControl? Pre-boot goes only to 20MB/s and UnitControl goes to 80MB/s, most recent versions of both. I don't get anywhere near the transfer speed without configuring drives with UnitControl, so ancient or not I'll stick with it.