Audio gets muted on track freeze and audio export operations

I have Cubase 6.5.4.161 with Artist version license. I use x86 version application because of the several rewire applications. I tried jBridge, but it is very inconvinient in some situations, so I just stick with x86 for now.

I have ASUS G74SX laptop that I use for my production. Mostly I use Waves plugins, Native Instruments Massive and Addictive Drums.

Very often I have severe problems with I try to export my project as audio or freeze a track that takes too much processing power.

For example: guitar track that is processed with X-Hum + X-Noise + Guitar Stomp + SSL EQ
When i freeze it in the beginning of the project everything works fine, but as the project gets bigger and bigger, and especially when I get to mixing point, when I freeze the above mentioned track there is no sound coming out of it after freeze operation.

At this stage export audio operation also becomes very buggy (most of the time). When I export in non-realtime some tracks are not exported at all (they behave like freeze operation behaves, no sound), when I export i realtime most of the time it works, but sometimes all of the audio gets muted after some point, so just part of the song is exported.

The strange thing is that when I just play it back everything is played as it’s supposed to. So when I hit this problem all I can to is send main out to coaxial output of my sound card (MBox 3) to another sound card and record it there.

I reviewed several posts in forum, there were several suggestions,
for example deleting “C:\Users<user>\AppData\Roaming\Steinberg\Cubase 6” folder. It worked once but not afterwords.

Please help me resolve this issue.
Thank you.