Could you please name the excact model of your CPU? 2.6 GHZ is'nt that much if you want to have high samplerates and low buffers for you soundcard. 96000 Hz is Pro studio audio and you CPU is not. ANd beside that then there is no need to go higher than 48000 Hz unless you have good reasons to do so.
You have your soundcard at a samplerate of 96000 Hz. What is your buffer settings?
Having tried the 2 preset you mention the way you tell to try it out, then i think it's most likely you are having latency issues. The fact you tell that most of your issues go away with a samplerate at 48000 support this.
can you please provide a screenshot that show the load of each of your CPU cores at the time you are having issues?
As you say you don't have issues in the standalone version, then which DAW do you use? Does your DAW have a setting that perhaps sound like it should help on latency but actually does the opposite when using softsynth like this? In example Studio Ones so called drop out protection should not be used for this.
I can see, that the Bass 101 preset has 5 unison voices. That means that you actually play 15 voices when you play 3 notes.
The Math Bass only have a unison setting at 2. But i don't find any issues in any of the presets unless i make a setting and play in a way where i get latency issues.
Keep in mind that the more voices you play, the more power you need. ANd the higher samplerate and the lower buffers you use, the more power you need.
EDIT: Also have you optimized your computer for audio performance? For Windows especially set it in high performance mode. There are guides out there. As you don't have issues when using the satndalone version, then i don't think this is your main issue, but it can give you better performance. EDIT END