diff --git a/FFMpegCore.Test/ArgumentBuilderTest.cs b/FFMpegCore.Test/ArgumentBuilderTest.cs
index f0792ef..18a8c7d 100644
--- a/FFMpegCore.Test/ArgumentBuilderTest.cs
+++ b/FFMpegCore.Test/ArgumentBuilderTest.cs
@@ -239,9 +239,8 @@ public void Builder_BuildString_Loop()
         [TestMethod]
         public void Builder_BuildString_Seek()
         {
-            var str = FFMpegArguments.FromFileInput("input.mp4", false, opt => opt.Seek(TimeSpan.FromSeconds(10)))
-                .OutputToFile("output.mp4", false, opt => opt.Seek(TimeSpan.FromSeconds(10))).Arguments;
-            Assert.AreEqual("-ss 00:00:10 -i \"input.mp4\" -ss 00:00:10 \"output.mp4\"", str);
+            var str = FFMpegArguments.FromFileInput("input.mp4", false, opt => opt.Seek(TimeSpan.FromSeconds(10))).OutputToFile("output.mp4", false, opt => opt.Seek(TimeSpan.FromSeconds(10))).Arguments;
+            Assert.AreEqual("-ss 00:00:10.000 -i \"input.mp4\" -ss 00:00:10.000 \"output.mp4\"", str);
         }
 
         [TestMethod]
diff --git a/FFMpegCore.Test/FFProbeTests.cs b/FFMpegCore.Test/FFProbeTests.cs
index 5ac83a1..a056fd9 100644
--- a/FFMpegCore.Test/FFProbeTests.cs
+++ b/FFMpegCore.Test/FFProbeTests.cs
@@ -25,6 +25,22 @@ public async Task Audio_FromStream_Duration()
             Assert.IsTrue(fileAnalysis.Duration == streamAnalysis.Duration);
         }
 
+        [TestMethod]
+        public void MediaAnalysis_ParseDuration()
+        {
+            var durationHHMMSS = new FFProbeStream { Duration = "05:12:59.177" };
+            var longDuration = new FFProbeStream { Duration = "149:07:50.911750" };
+            var shortDuration = new FFProbeStream { Duration = "00:00:00.83" };
+
+            var testdurationHHMMSS = MediaAnalysis.ParseDuration(durationHHMMSS);
+            var testlongDuration = MediaAnalysis.ParseDuration(longDuration);
+            var testshortDuration = MediaAnalysis.ParseDuration(shortDuration);
+
+            Assert.IsTrue(testdurationHHMMSS.Days == 0 && testdurationHHMMSS.Hours == 5 && testdurationHHMMSS.Minutes == 12 && testdurationHHMMSS.Seconds == 59 && testdurationHHMMSS.Milliseconds == 177);
+            Assert.IsTrue(testlongDuration.Days == 6 && testlongDuration.Hours == 5 && testlongDuration.Minutes == 7 && testlongDuration.Seconds == 50 && testlongDuration.Milliseconds == 911);
+            Assert.IsTrue(testdurationHHMMSS.Days == 0 && testshortDuration.Hours == 0 && testshortDuration.Minutes == 0 && testshortDuration.Seconds == 0 && testshortDuration.Milliseconds == 830);
+        }
+
         [TestMethod]
         public async Task Uri_Duration()
         {
diff --git a/FFMpegCore/Assembly.cs b/FFMpegCore/Assembly.cs
new file mode 100644
index 0000000..0117671
--- /dev/null
+++ b/FFMpegCore/Assembly.cs
@@ -0,0 +1,3 @@
+using System.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("FFMpegCore.Test")]
\ No newline at end of file
diff --git a/FFMpegCore/FFMpeg/Arguments/SeekArgument.cs b/FFMpegCore/FFMpeg/Arguments/SeekArgument.cs
index 1057b88..1b58890 100644
--- a/FFMpegCore/FFMpeg/Arguments/SeekArgument.cs
+++ b/FFMpegCore/FFMpeg/Arguments/SeekArgument.cs
@@ -8,11 +8,28 @@ namespace FFMpegCore.Arguments
     public class SeekArgument : IArgument
     {
         public readonly TimeSpan? SeekTo;
+
         public SeekArgument(TimeSpan? seekTo)
         {
             SeekTo = seekTo;
         }
-        
-        public string Text => !SeekTo.HasValue ? string.Empty : $"-ss {SeekTo.Value}";
+
+        public string Text {
+            get { 
+                if(SeekTo.HasValue)
+                {
+                    int hours = SeekTo.Value.Hours;
+                    if(SeekTo.Value.Days > 0)
+                    {
+                        hours += SeekTo.Value.Days * 24;
+                    }
+                    return $"-ss {hours.ToString("00")}:{SeekTo.Value.Minutes.ToString("00")}:{SeekTo.Value.Seconds.ToString("00")}.{SeekTo.Value.Milliseconds.ToString("000")}";
+                }
+                else
+                {
+                    return string.Empty;
+                }
+            }
+        }
     }
 }
diff --git a/FFMpegCore/FFProbe/MediaAnalysis.cs b/FFMpegCore/FFProbe/MediaAnalysis.cs
index 1ee7b18..772997a 100644
--- a/FFMpegCore/FFProbe/MediaAnalysis.cs
+++ b/FFMpegCore/FFProbe/MediaAnalysis.cs
@@ -18,7 +18,7 @@ private MediaFormat ParseFormat(Format analysisFormat)
         {
             return new MediaFormat
             {
-                Duration = TimeSpan.Parse(analysisFormat.Duration ?? "0"),
+                Duration = ParseDuration(analysisFormat.Duration),
                 FormatName = analysisFormat.FormatName,
                 FormatLongName = analysisFormat.FormatLongName,
                 StreamCount = analysisFormat.NbStreams,
@@ -66,7 +66,6 @@ private VideoStream ParseVideoStream(FFProbeStream stream)
             };
         }
 
-
         private AudioStream ParseAudioStream(FFProbeStream stream)
         {
             return new AudioStream
@@ -115,11 +114,41 @@ public static int ParseIntInvariant(string line) =>
             int.Parse(line, System.Globalization.NumberStyles.Any, System.Globalization.CultureInfo.InvariantCulture);
         
         
+        public static TimeSpan ParseDuration(string duration)
+        {
+            if (!string.IsNullOrEmpty(duration))
+            {
+                var match = DurationRegex.Match(duration);
+                if (match.Success)
+                {
+                    // ffmpeg may provide < 3-digit number of milliseconds (omitting trailing zeros), which won't simply parse correctly
+                    // e.g. 00:12:02.11 -> 12 minutes 2 seconds and 110 milliseconds
+                    var millisecondsPart = match.Groups[4].Value;
+                    if (millisecondsPart.Length < 3)
+                    {
+                        millisecondsPart = millisecondsPart.PadRight(3, '0');
+                    }
+
+                    var hours = int.Parse(match.Groups[1].Value);
+                    var minutes = int.Parse(match.Groups[2].Value);
+                    var seconds = int.Parse(match.Groups[3].Value);
+                    var milliseconds = int.Parse(millisecondsPart);
+                    return new TimeSpan(0, hours, minutes, seconds, milliseconds);
+                }
+                else
+                {
+                    return TimeSpan.Zero;
+                }
+            }
+            else
+            {
+                return TimeSpan.Zero;
+            }
+        }
+
         public static TimeSpan ParseDuration(FFProbeStream ffProbeStream)
         {
-            return !string.IsNullOrEmpty(ffProbeStream.Duration)
-                ? TimeSpan.Parse(ffProbeStream.Duration)
-                : TimeSpan.Parse(TrimTimeSpan(ffProbeStream.GetDuration()) ?? "0");
+            return ParseDuration(ffProbeStream.Duration);
         }
 
         private static string? TrimTimeSpan(string? durationTag)