Orthogonal Thought | Random musings from the creator of Cooking For Engineers and Lead Architect of Fanpop




Fixing SONOS "Unable to play" song / "Unable to connect" to local music library problem on Windows 7

Posted 7 November, 2014 at 4:52pm by Michael Chu
(Filed under: Personal Computers)

In general, I've been quite pleased with my Sonos units, but I've been plagued with a problem accessing my personal music library for more than a few days at a time. I think i have a fix for my problems now.

I run the Sonos application on a Windows 7 machine which I use as a file server and media server (running a variety of transcoding software for various devices around the house). My music library is stored on a local drive on that machine (this detail is probably unimportant as Sonos never accesses the library locally and always uses the network share for the library). My first problem was the Error 900 problem which occurs when the stack size of the network server is too small to buffer the data (or something). The solution was to use regedit (Start->Run->regedit.exe) and modify key:
from the default value of 15 (decimal) to either 18 or 24 (decimal). I upped mine to 24 and it got rid of the Error 900 problem, but I would still routinely lose connection to the music library. (See Sonos Error 900 FAQ.)

When I say "lose connection", I mean that when I try to play a particular song I get the following error:
Unable to play 'SONG NAME' - unable to connect to //SERVER_NAME/Music

In addition, when browsing through my albums, the album images do not load (this is a faster/easier test so for months I used this quick check to see if I'd lost the ability to connect to the music library or not). When I contacted Sonos Customer Service, they suggested I try increasing the IRPStackSize in increments of 3 (but didn't recommend going past 24) as well as disabling other shares on the server (not an option). I did find that restarting the Windows Server service (Services -> Server -> Restart service) which did allow Sonos to reconnect so for a while I did that and eventually wrote a batch command that I could issue to speed up the process. However, that still meant that the library was unavailable most of the time and needed manual intervention to get it to reconnect (not ideal when trying to explain the process to my wife).

A couple weeks ago, I found a fix related to other network limit issues that seems to work in resolving this library issue. I used regedit and modified key:
and set it to 3 and have not had a problem since. No more service restarts; no more "unable to play" and "unable to connect" errors.