diff --git a/pkg/media/input.go b/pkg/media/input.go
index aa6a8b4e..c8beb621 100644
--- a/pkg/media/input.go
+++ b/pkg/media/input.go
@@ -35,6 +35,7 @@ import (
 
 type Source interface {
 	GetSources() []*gst.Element
+	ValidateCaps(*gst.Caps) error
 	Start(ctx context.Context) error
 	Close() error
 }
@@ -126,6 +127,28 @@ func (i *Input) Close() error {
 }
 
 func (i *Input) onPadAdded(_ *gst.Element, pad *gst.Pad) {
+	var err error
+
+	defer func() {
+		if err != nil {
+			msg := gst.NewErrorMessage(i.bin.Element, err, err.Error(), nil)
+			i.bin.Element.GetBus().Post(msg)
+		}
+	}()
+
+	typefind, err := i.bin.GetElementByName("typefind")
+	if err == nil && typefind != nil {
+		var caps interface{}
+		caps, err = typefind.GetProperty("caps")
+		if err == nil && caps != nil {
+			err = i.source.ValidateCaps(caps.(*gst.Caps))
+			if err != nil {
+				logger.Infow("input caps validation failed", "error", err)
+				return
+			}
+		}
+	}
+
 	// surface callback for first audio and video pads, plug in fakesink on the rest
 	i.lock.Lock()
 	newPad := false
@@ -156,11 +179,16 @@ func (i *Input) onPadAdded(_ *gst.Element, pad *gst.Pad) {
 		}
 		pad = ghostPad.Pad
 	} else {
-		sink, err := gst.NewElement("fakesink")
+		var sink *gst.Element
+
+		sink, err = gst.NewElement("fakesink")
 		if err != nil {
 			logger.Errorw("failed to create fakesink", err)
+			return
 		}
-		pads, err := sink.GetSinkPads()
+		var pads []*gst.Pad
+
+		pads, err = sink.GetSinkPads()
 		pad.Link(pads[0])
 		return
 	}
diff --git a/pkg/media/rtmp/appsrc.go b/pkg/media/rtmp/appsrc.go
index f57353bb..34545365 100644
--- a/pkg/media/rtmp/appsrc.go
+++ b/pkg/media/rtmp/appsrc.go
@@ -111,6 +111,23 @@ func (s *RTMPRelaySource) GetSources() []*gst.Element {
 	return []*gst.Element{s.flvSrc.Element}
 }
 
+func (s *RTMPRelaySource) ValidateCaps(caps *gst.Caps) error {
+	if caps.GetSize() == 0 {
+		return errors.ErrUnsupportedDecodeFormat
+	}
+
+	str := caps.GetStructureAt(0)
+	if str == nil {
+		return errors.ErrUnsupportedDecodeFormat
+	}
+
+	if str.Name() != "video/x-flv" {
+		return errors.ErrUnsupportedDecodeFormat
+	}
+
+	return nil
+}
+
 type appSrcWriter struct {
 	appSrc *app.Source
 	eos    *atomic.Bool
diff --git a/pkg/media/urlpull/source.go b/pkg/media/urlpull/source.go
index 772cadbb..a896046d 100644
--- a/pkg/media/urlpull/source.go
+++ b/pkg/media/urlpull/source.go
@@ -23,6 +23,19 @@ import (
 	"github.com/livekit/ingress/pkg/params"
 )
 
+var (
+	supportedMimeTypes = []string{
+		"audio/x-m4a",
+		"application/x-hls",
+		"video/quicktime",
+		"video/x-matroska",
+		"video/webm",
+		"audio/ogg",
+		"application/x-id3",
+		"audio/mpeg",
+	}
+)
+
 type URLSource struct {
 	params *params.Params
 	src    *gst.Element
@@ -85,6 +98,25 @@ func (u *URLSource) GetSources() []*gst.Element {
 	}
 }
 
+func (s *URLSource) ValidateCaps(caps *gst.Caps) error {
+	if caps.GetSize() == 0 {
+		return errors.ErrUnsupportedDecodeFormat
+	}
+
+	str := caps.GetStructureAt(0)
+	if str == nil {
+		return errors.ErrUnsupportedDecodeFormat
+	}
+
+	for _, mime := range supportedMimeTypes {
+		if str.Name() == mime {
+			return nil
+		}
+	}
+
+	return errors.ErrUnsupportedDecodeFormat
+}
+
 func (u *URLSource) Start(ctx context.Context) error {
 	return nil
 }
diff --git a/pkg/media/whip/whipsrc.go b/pkg/media/whip/whipsrc.go
index 08663972..1b5dc6b1 100644
--- a/pkg/media/whip/whipsrc.go
+++ b/pkg/media/whip/whipsrc.go
@@ -102,6 +102,10 @@ func (s *WHIPSource) GetSources() []*gst.Element {
 	return ret
 }
 
+func (s *WHIPSource) ValidateCaps(*gst.Caps) error {
+	return nil
+}
+
 func (s *WHIPSource) getRelayUrl(kind types.StreamKind) string {
 	return fmt.Sprintf("%s/%s", s.params.RelayUrl, kind)
 }