diff --git a/lib/sink_iface.h b/lib/sink_iface.h
index 15ea952..0d1b8e6 100644
--- a/lib/sink_iface.h
+++ b/lib/sink_iface.h
@@ -32,6 +32,8 @@
 class sink_iface
 {
 public:
+  virtual ~sink_iface() = default;
+
   /*!
    * Get the number of channels the underlying radio hardware offers.
    * \return the number of available channels
diff --git a/lib/source_iface.h b/lib/source_iface.h
index 14f05bb..02e4da3 100644
--- a/lib/source_iface.h
+++ b/lib/source_iface.h
@@ -32,6 +32,8 @@
 class source_iface
 {
 public:
+  virtual ~source_iface() = default;
+
   /*!
    * Get the number of channels the underlying radio hardware offers.
    * \return the number of available channels