Have you tried the
http://bis-pool.net/ miner? It usually only uses a few % on the CPU, so it might run better in the background. If it still doesn't run OK, you could increase "delay_between_batches" (measured in ms) in the config file
Much better!!!! Thank you very much!!! And is there anyway to see how much coins obtained at this pool? At my miner details of pool site I can see only hashrate and number of miners...