I had an issue where sometimes when playing songs on a library server client, switching to another song would take a long time...many times around 8-10 seconds...occasionally long enough to get a time-out error. Yet at other times, the next track would begin to play instantly, or certainly in under 2 seconds.
I won't bore you with the troubleshooting steps I took to determine if it was an MC issue with transcoding or buffering, or if it was a network issue.
Turns out it was a network issue, caused by another software that was running on the library server machine.
The software handles online backups and copies newly modified files up to the cloud a couple of times a day.
From the client location, I couldn't tell when it was running and when it wasn't.
Anyway, for some reason, that software was getting more of my internet's upload bandwidth than MC was.
The solution was to modify QOS (quality of service) settings in Windows in order to elevate MC's priority above the other program. So now if both programs need bandwidth, and there's not enough to satisfy both of them, MC gets it first.
These how-to steps are for Windows7 but may work on other versions of Windows.
1) Make sure your network card has QOS enabled.
Start > Control Panel > Network and Sharing Center
Click on Change Adapter Settings
Right-click on your network connection and choose "properties"
Make sure the box is checked for "QOS Packet Scheduler"
Click OK
2) Run the Local Group Policy Editor
C:\windows\System32\gpedit.msc
Local Computer Policy > Computer Configuration > Windows Settings > Policy-based QOS
3) Create a new policy to elevate MC's priority
Right-click on Policy-based QOS and choose "create new policy" and fill in these values:
POLICY NAME = MC
SPECIFY DSCP VALUE = 32
Click NEXT
Click radio button for "only applications with this executable name"
Fill in Media Center 15.exe for the application name
Click NEXT
Don't change anything on this page
Click NEXT
Don't change anything on this page
Click FINISH
4) Create a new policy to elevate MC's service priority
Right-click on Policy-based QOS and choose "create new policy" and fill in these values:
POLICY NAME = MC Service
SPECIFY DSCP VALUE = 32
Click NEXT
Click radio button for "only applications with this executable name"
Fill in JRService.exe for the application name
Click NEXT
Don't change anything on this page
Click NEXT
Don't change anything on this page
Click FINISH
5) Create a new policy to reduce the offending program's priority
Right-click on Policy-based QOS and choose "create new policy" and fill in these values:
POLICY NAME = Name of the program
SPECIFY DSCP VALUE = 12
Click NEXT
Click radio button for "only applications with this executable name"
Fill in the executable filename for the application name
Click NEXT
Don't change anything on this page
Click NEXT
Don't change anything on this page
Click FINISH
repeat step 5 if desired, for any other programs.
Close the Group Policy editor and reboot your computer.