1-8 not working

[johnathanriddle]

So I have had this board since last year, ctb16pc. It worked for a few days during the show last year just fine. Then it stopped. channels 9-16 work no problem, but 1-8 don't really. Well they do its just takes like a hour for them to turn on, like the board has to warm up or something...I took it apart twice last year and re soldered all of the joints. Well that never fixed it... Today I got along to working on it again, I did the same thing, cleaned all terminals then tested the board. It worked fine without being in the heat sinks, once I got it in the heat sinks and enclosure it went back to doing the exact same thing. I'm honestly confused on what could be doing this. I've built 8 boxes from scratch over the last two years and all have been fine. This one is just giving me fits. Any ideas?