Cannot stop a call and start a new call

[astaikos316]

Describe the bug
Have built an application in unity using the master branch where i start a call between 2 peers and everything works fine. I then end the call and try to start a new call and I get the following error when trying to start the new call and no video or audio starts to pass but connection is established:

ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
System.ThrowHelper.ThrowArgumentOutOfRangeException (System.ExceptionArgument argument, System.ExceptionResource resource) (at <437ba245d8404784b9fbab9b439ac908>:0)
System.ThrowHelper.ThrowArgumentOutOfRangeException () (at <437ba245d8404784b9fbab9b439ac908>:0)
System.Collections.Generic.List`1[T].get_Item (System.Int32 index) (at <437ba245d8404784b9fbab9b439ac908>:0)
Microsoft.MixedReality.WebRTC.Unity.PeerConnection.StartConnection () (at Assets/Microsoft.MixedReality.WebRTC.Unity/Scripts/PeerConnection.cs:912)

In my project I call PeerConnection.StartConnection() to start the call and PeerConnection.Uninitialize() and PeerConnection.Close() to stop the connection.

To Reproduce
Start a Peer to Peer call. End a Peer to Peer call and then try to start a new peer to peer call.

Expected behavior
Should be able to start and stop calls without having to fully quit application

Environment

• Platform: Unity Editor to WIndows Standalone build
• Architecture: Unity Editor is x64 on Windows and build is x64
• Unity version (if applicable): 2019.3.9f1
• Target device: Windows Desktop

[astaikos316]

@djee-ms @fibann just wondering if anyone has had a change to dig into this issue a little deeper. I have not be able to come to any conclusions through my attempts of troubleshooting.

[fibann]

@astaikos316 no updates for the moment, but this is on the backlog for 2.0 so we should have a look at this soon.

[fibann]

@astaikos316 in reply to #343 (comment): this should be done now, the relevant code has been refactored (you now start/stop a connection by enabling/disabling the PeerConnection component).

[astaikos316]

@fibann I have updated to the recent 2.0 preview release and trying this out. I am having an issue between a Hololens 2 and a PC build. When I start a call from the PC to Hololens, everything works well. However when I start a calls from the Hololens 2, I get an "cannot apply remote description object not initialized" error on the Hololens and then subsequent calls fail and the Hololens 2 app crashes. I am getting the log message from an In-Game Debug Console window on the Hololens so I cannot get much detail about what "object" is not initializing. Any ideas of where I should look?

[fibann]

@astaikos316 could you open a new issue filling in platform details, SDP messages, etc.?

[astaikos316]

@fibann Just opened new issue #498

[astaikos316]

@fibann @djee-ms I have been working with 2.0 release and have found that starting/stopping a connection by enabling/disabling the PeerConnection component starts a new call, however the video is not sent from either endpoint but the audio is sent between them.

[fibann]

@astaikos316 could you open a new issue filling in platform details, SDP messages, etc.? Things that would be useful:

• comparing SDP messages from the first connection attempt to the ones from the second attempt and search for differences among the video lines
• put a breakpoint in the (I420A|Argb32)VideoFrameReady handlers on the receiving side and checking if frames are being received or no
• run a debug build of MR-WebRTC on both hosts, get the WebRTC debug logs and look for something suspicious

FWIW I did a quick test with the VideoChatDemo Unity sample and TestAppUWP and everything worked fine.

[astaikos316]

@fibann I just opened Issue #535. Provided a little more detail after running some experiments this morning.