ROM Performance Degrades Over Time

[pkmgarf]

So, the first time I had this problem, I thought I was imagining things. But now, it's popped up on a few ROMS (Manilla and Titanium). Everything seems to work fine right after flashing, but then, after some time (days?), things start going wrong.

The phone starts lagging really badly, text entry becomes painstakingly slow, and the phone will freeze overall (sometimes it comes back, sometimes I reset). I love my Diamond...but would LOVE to know why this is happening. Running CleanRAM seems to help for a few minutes/hours, but not long...

Ideas?