Need Help! Issues with Traktor

I haven't posted on here in a long time.
I need help with a traktor issue. I don't know what the problem is, I've tried everything.
I recorded a mix back in october and when I checked the outcome of it in traktor and ableton, the levels didn't change when I played a track over another and the quality didn't change when I changed the tempo. I matched recorder's output gain to zero out the auto gain of the tracks. so a track that had an auto-gain of -1.5db, I would set the recorder gain to 1.5. I haven't changed it at all since.
The wave forms of each track in the mix looked exactly as they did as a stand alone track. In other words, the levels were pretty much perfect!
This is what tracks look like. Track: Burial (Skrillex & Trollphace remix)
In October:
Attachment 26499

This month:
Attachment 26500

This what it looked like when I mashed or played tracks over another:
Attachment 26495
This is what the transition between Hellcat (Snails Remix) from MUST DIE! and King is back from Snails looked like in october.
I record it again and this is what it looks like
Attachment 26496
I didn't change the auto-gain of either of the tracks nor the output gain of the recorder. I don't know what happened.
The overall gain of the mix get's lowered when I mash songs together. I've tried everything to find the problem.
I've checked every filter type, every EQ type. I've adjusted the headroom between -3db to -9db, it may be the limiter but I don't play around with the limiter.
If anybody can help me with this I would be very appreciative. I'm trying to get this mix on an online radio show and I don't want there to be any issues!
Thanks again for the help!