The 1.5.0 patch has made in-game streaming worse for me. Now after like 10-15 minutes of playing the game starts accessing the HDD like crazy and the game slows down to a halt. This never happened till 1.4.0. Piloting and driving has become nigh-impossible and my frame-rate has taken a hit as well. This sucks.
This has happened to me a couple of times. An Alt-Tab out and back in fixes it on my end.