Importing audio CD some tracks ok some with gaps with no audio

Team, when importing audio CDs into iTunes on the iMac some tracks will import fine while others may have a 30-90 second 'blank spot' where there is no audio at all...and then the track continues (with that part of the song that was 'blank spot' missing). Seems to be getting a little worse and seems to be independent of import settings. The 5 year old watches DVDs on the iMac with no issues. Any thoughts? The Imac is only 18 months old. Thanks.