The problem is caused by dell's wifi cards, the 1395 seems particularly bad. It causes latency which is so high when it tries to find a signal the sound will cut out.

Drove me mad. Double click on wirless network icon. Refresh the servers. If it stutters/skips then, you have this problem.

I replaced mine with an intel based card (the 4965) and now the problem has dissapeared. The sound may skip when the processor is at 100% such as during a virus scan or something but thats to be expected.

The audio of the dell 1520 (which is like your vostro 1500) is now crystal clear and never stutters. Even the stutter when starting up windows has gone.

So stange but true. If your audio skips don't try a new sound card (many did and didn't work!), upgrade your wifi. A 4965 intel wifi minicard on ebay costs just