More issues. Decided to try LP EQ )Cakewalk) today. Placed it on Synth audio track. Set "Reduce Honk and Mud" preset. First I had audio dropout with loud noize, then I had delayed Play (like 10-20 seconds long before playback starts), and then my Bass track (Midi with Rob Papen Sub Boom) plays every other note (2 instead of 4) and another track that plays chords massed up. Restarted computer, restarted Sonar. The same thing. Delete LP EQ- everything is back to normal. Insert it again- back to playing 2 out of 4 notes. Any ideas? Thank you. 

Have you tried selecting the option for low latency, you can find it in Advanced Options (I think)
 
[edit] it's actually 'Expert' mode, found at the lower left hand side, Precision - Non Linear

Do you have your i/o setup for linear phase plugins? LP uses look ahead buffers. I keep my i/o buffers small while I record and mix for low latency, but if I use LP when mastering I enlarge the buffers.

This is my new computer, I did not try Look Ahead plugins yet. This is worrisome, as I use Izotope Nectar 2 vocal and ozone/Neutron, those also look ahead. 
 
You mean increase Latency on Audio Interface control panel? That would be inconvenience to do- it would affect all software synths. I am not mastering, I just wanted to make it less bassy... There other EQs, but just wondering what's wrong with this one. 
 
There is no Options. You mean Preferences? Thank you. 

Dropped MIDI notes are a symptom of too small a value for "Prepare using nnn Millisecond Buffer" in Preferences > MIDI > Playback and Recording.
 
Also consider setting the Precision in the Expert menu of the L-Phase plug-ins to Non-Linear when tracking with the plug-ins. The linear modes are intended for mixing and mastering.

The track I had it inserted is already committed (frozen) to Audio. If I am not recording, this means I am mixing. I dont see how it would affect MIDI on ANOTHER track. Also missing notes being not triggered have different feel. Those are usually first notes in the measure. This actually changed the rhythm patters and plays selectively 2 out of 4 notes (first and 3rd) in each measure. 
 
But thank you, i will test these settings.