[Fatal Error] :1:2: Reference is not allowed in prolog

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cmnz
Posts: 3
Joined: Sat Jul 19, 2025 7:27 pm

[Fatal Error] :1:2: Reference is not allowed in prolog

Post by cmnz »

UMS is giving me the error "[Fatal Error] :1:2: Reference is not allowed in prolog" in the logs several times a second. The server app seems to be using a lot of CPU without even playing anything. This started happening when I recently went from version 9.3.1-1 to 14.12.1, and it is still doing it after I just updated to 14.13.0. Can someone please help with this?

The zipped log files are too big for the forum so I have put it here https://mega.nz/file/okgBlJxJ#EgNMjRAim ... Qq3E-rKjBg
Screenshot of the error here:
Image
https://mega.nz/file/EgxGGBAQ#5wo8JAsHY ... UG_WZXVMh4
Last edited by cmnz on Thu Aug 07, 2025 7:50 am, edited 1 time in total.
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mik_s
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Re: [Fatal Error] :1:2: Reference is not allowed in prolog

Post by mik_s »

Not sure what is going on here, I can't see anything obvious that is causing it in the logs.

One strange thing is the size of the logs, they are over 200MB fully extracted for only a few seconds.
They normally should not be large enough that they cannot be uploaded to the forum.
I don't see any error messages besides the prolog and there is not enough of them to make the logs that big.

I do see the same message being constantly spammed and this will be the cause of the file size.

Code: Select all

ServerSentEvents send message: {"id":3,"name":"APTV_9","address":"192.168.20.9","uuid":"898f9738-d930-4db4-a3cf-d80f99888515","icon":"wmp.png","iconOverlays":"","playing":" ","time":" ","progressPercent":0,"userId":-1,"state":{"playback":0,"mute":false,"volume":50,"buffer":0,"name":" "},"isActive":true,"isAllowed":true,"isAuthenticated":false,"controls":3,"action":"renderer_update"}
This is part of the data that is sent to the webUI for UMS to update the status of renderers but something is triggering it every few milliseconds.

I think this is the request received as it appears just as often. It seems to be reporting the current volume on the TV.

Code: Select all

Received a request from 192.168.20.9:
============================= UPNP HTTP SERVER REQUEST BEGIN ================================
NOTIFY /dev/898f9738-d930-4db4-a3cf-d80f99888515/svc/upnp-org/RenderingControl/event/cb HTTP/1.1

HEADER:
...

CONTENT:
<e:propertyset xmlns:e="urn:schemas-upnp-org:event-1-0">
    <e:property>
        <LastChange>&lt;Event xmlns="urn:schemas-upnp-org:metadata-1-0/RCS/"&gt;&lt;InstanceID val="0"&gt;&lt;Volume Channel="Master" val="50"/&gt;&lt;Mute Channel="Master" val="0"/&gt;&lt;PresetNameList val="FactoryDefaults"/&gt;&lt;VolumeDB Channel="Master" val="0"/&gt;&lt;/InstanceID&gt;&lt;/Event&gt;</LastChange>
    </e:property>
</e:propertyset>

============================= UPNP HTTP SERVER REQUEST END ==================================
I searched for what "Reference is not allowed in prolog" and found an instance about escaping XML like <> to &lt;&gt for data like it does here and this might not be working right if UMS cannot keep up.

This APTV_9 is confusing me as it is the same IP as the Sony TV so maybe there is an app on the TV that is spamming requests to UMS and maybe it is overwhelming it and causes that error. This will be the cause of high CPU too.

I could not find any info on APTV_9 but it also has in the manufacturer tag as being from WaxRain which is some Airplay screen mirroring app.
Do you have something like this installed on the TV? If so try disabling it and see if stops doing this.
Logs are important for us to help, Please follow This Link before asking for support. Just a forum cleaner, Will help if I can but no expert.
cmnz
Posts: 3
Joined: Sat Jul 19, 2025 7:27 pm

Re: [Fatal Error] :1:2: Reference is not allowed in prolog

Post by cmnz »

Thanks, that's very helpful. I removed the Airpin app from the Sony TV and that seems to have stopped the constant error message. I can't remember if I installed that or it was pre-installed but I'm not using it now. It's a screen mirroring app from Waxrain.
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mik_s
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Re: [Fatal Error] :1:2: Reference is not allowed in prolog

Post by mik_s »

Glad that was the cause and it is now working correctly.

I'll make an issue on Github about this to see if there is anything to prevent apps on devices from constantly spamming requests and block or ignore them
Logs are important for us to help, Please follow This Link before asking for support. Just a forum cleaner, Will help if I can but no expert.
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