sick ofn pops and drop outs

i swear to god im about to blow my head off if i dont figure out how to get rid of these pops and drop out.I have tryed everything so far like changin buffers and going threw tech support but nothin works.most of my pre installed sonar 8 studio plugins work but my ik sonic synth is kinda freaking out to and thats the one i really like.when i went threw tech support they made me change my buffer to 256,uncheck 64 bit precision,raise my latency to maximam on my tascam us 144 but all this ive tryed before and didnt work.on most sounds of my vsts are performing good but there are alot that pop so i dont know if they are just high rate samples that take it out of wack.I gotta figure out a way to fix this cause theres no way im gonna buy another interface just because of a dam soundcard,there are people out there that are working with worse things and still figure it out.