"Gtk_range_set_range: assertion 'min <= max' failed"

Hello,

I am not sure if this project is still active, but I just solved a problem in my system. When loading a new music file in Playitslowly, end position cursor used to return to 0 and the app reported the error of the title when pressing "Play" button. After a few tries it worked, but it remained an annoying issue.

Today that I had some time to look into it I found out that Gstreamer's query_position() and query_duration() returned false and -1 the first few times they were called and thus endchooser variable got a wrong value. I worked around this issue by looping the above function calls until they return True, as shown in my diff file attached.

Questions from my side:
1. Any ideas why this problem appeared? Is it only me or other users have the same issue? Let me know if you want any info about the versions I use.
2. I am not a Gstreamer expert, but I suspect that in the solution I have provided there may be an infinite loop under certain conditions. Any suggestions for a more elegant way to solve the issue?

Regards,
Stelios

Attached:
[diff_changes_playitslowly.txt](https://github.com/jwagner/playitslowly/files/5749192/diff_changes_playitslowly.txt)

Start by reviewing the attached diff and the code that calls GStreamer's query_position() and query_duration() before the endchooser value is used when Play is pressed. Reproduce the initial failed queries and inspect how the range is set. Done means the end position remains valid when queries return false or -1, without an unbounded retry.

Written by the indexing model from the issue text.