After a week of pretending that there were no real problems, Microsoft has finally admitted that playing music in Vista throttle's network performance significantly.

Writing in his blog, Microsoft's Mark Russinovich acknowledged a bug with Vista's network programming that can noticeably slow down file transfers on a local network if you play music at the same time.

Russinovich said that the bug in the NDIS throttling code magnifies if you have multiple NICs.

A system with both wireless and wired adapters will process at most 8000 packets per second, and with three adapters it will process a maximum of 6000 packets per second. 6000 packets per second equals 9MB/s, a limit that’s visible even on 100Mb networks.

More here.