When I was young I have a cassette tape bought by my mum and it's just a pirate version of various classical music bundled together but consists of mainly Strauss Jr. (The first title is Blue Danube and others like T-T Polkas, etc.) The first one on the side B is a very soothing piece of music but however hard I searched the internet I couldn't identify it. It does not sounds like Strauss style but since the album title says Strauss I searched tens of albums but couldn't find a match.
I used LMMS to transcribe & compose the first ~20s of notes and made a mp3 file hope someone who knows more lot than me can help me identify it. I'm pretty sure the notes in my mind are correct.
UPDATED：Another clue is that the title of this music is somewhat related to "Morning" or "Morgen". It's a symphony played by orchestra, not any solo nor trios.