Hi, I am trying to ingest a RTSP stream using GPAC, however, everytime I am trying, I get the following error:

`[RTSP] Error processing user command Network Unreachable`

Here are the commands used:

# to run the rtsp server

`docker run --rm -it --network=host aler9/rtsp-simple-server`

# ffmpeg sending a looped stream to the server 

`ffmpeg -re -stream_loop -1 -i test_30fps.mp4 -c copy -f rtsp rtsp://localhost:8554/mystream`

# GPAC grabbing the stream from the server and putting it into an MP4 file:

`gpac  rtpin:src=rtsp://192.168.1.32:8554/mystream:gpac:ifce=wlp92s0:FID=SOURCE reframer:rt=on:SID=SOURCE:FID=REGULATED @ -o out.mp4 -graph -logs=all@info -log-file=rtsp.log`

Of course, using ffplay works perfectly 

`ffplay rtsp://192.168.1.32:8554/mystream` => has no issue

All the files for this issue are here:
- server.log is the server of the rtsp server https://github.com/aler9/rtsp-simple-server
- rtsp.log is the log of the GPAC command

Configuration:
Ubuntu 21.10
GPAC version 8b22f0912dc91603136e0ddb3d2b583cb04d2c35 compiled manually following the instructions on the wiki

----

Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

- [x] I looked for a similar issue and couldn't find any.
- [x] I tried with the latest version of GPAC. Installers available at http://gpac.io/downloads/gpac-nightly-builds/
- [x] I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). I can share files anonymously with this dropbox: https://www.mediafire.com/filedrop/filedrop_hosted.php?drop=eec9e058a9486fe4e99c33021481d9e1826ca9dbc242a6cfaab0fe95da5e5d95

Detailed guidelines: http://gpac.io/2013/07/16/how-to-file-a-bug-properly/

Flaky RTSP input
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Flaky RTSP input
Issue date:

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Hi, I am trying to ingest a RTSP stream using GPAC, however, everytime I am trying, I get the following error:

`[RTSP] Error processing user command Network Unreachable`

Here are the commands used:

# to run the rtsp server

`docker run --rm -it --network=host aler9/rtsp-simple-server`

# ffmpeg sending a looped stream to the server 

`ffmpeg -re -stream_loop -1 -i test_30fps.mp4 -c copy -f rtsp rtsp://localhost:8554/mystream`

# GPAC grabbing the stream from the server and putting it into an MP4 file:

`gpac  rtpin:src=rtsp://192.168.1.32:8554/mystream:gpac:ifce=wlp92s0:FID=SOURCE reframer:rt=on:SID=SOURCE:FID=REGULATED @ -o out.mp4 -graph -logs=all@info -log-file=rtsp.log`

Of course, using ffplay works perfectly 

`ffplay rtsp://192.168.1.32:8554/mystream` => has no issue

All the files for this issue are here:
- server.log is the server of the rtsp server https://github.com/aler9/rtsp-simple-server
- rtsp.log is the log of the GPAC command

Configuration:
Ubuntu 21.10
GPAC version 8b22f0912dc91603136e0ddb3d2b583cb04d2c35 compiled manually following the instructions on the wiki

----

Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

- [x] I looked for a similar issue and couldn't find any.
- [x] I tried with the latest version of GPAC. Installers available at http://gpac.io/downloads/gpac-nightly-builds/
- [x] I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). I can share files anonymously with this dropbox: https://www.mediafire.com/filedrop/filedrop_hosted.php?drop=eec9e058a9486fe4e99c33021481d9e1826ca9dbc242a6cfaab0fe95da5e5d95

Detailed guidelines: http://gpac.io/2013/07/16/how-to-file-a-bug-properly/

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