Cubase ASIO spikes and stuttring on Playback

I am getting ASIO spikes almost in 50% of my song pl;ay back !
I have 4g ram , almost a ter in harddrive if I saying it right , Win 7 pro 64bit. I have tried everything from the form except renaming the file . I’m not really that computer suvey so If someone would give me a step by step explaination of what to do I really would be so greatful !!! I am trying to release my CD by the first week of MAY . But the spikes are stopping me from completing my project! I am open for any suggestions … Thanks and God Bless

Apart from that you´re in the german forum - with ASIO spikes, it might be helpful to tell people which soundcard you´re using

my sound card is ,SBT-SP6C/ 6-channel 3D PCI Sound Card.
I’m using Zoom R24 for my interface also.