Is the LNB a universal one? If it is, try setting the LNB Lo to just 10600, rather than universal and see if that makes a difference. The recent "fixes" had to do with 22khz switching, maybe if 22 khz is disabled in the receiver, it might make a difference?
When you downgraded the firmware, did it have you go through and select between FTA mode and Glorystar mode, country, language, etc? IIRC, there was a few times I downgraded and it did what yours is doing, it didn't go through the pick mode, country, etc and I actually had to do the hold the buttons thing with the firmware I wanted on a thumb drive in the front USB port to get it to actually downgrade, it wouldn't do it through the menu.
I am out of the loop quite a bit here, the last firmware I used was 9XX and I haven't worked on my 3500 for quite a long time, so things could be quite different now. I know some things are different, just from what people post up about the latest firmwares.
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