Advice: XM6, Momentum 4, or something else to look into.

Hello! I have a tough choice to make in regards to headphones. I have tried the Sony XM6 and Sennheiser Momentum 4 headphones, sadly, both left me disappointed in at least one area hence I have a few questions!

Momentum 4:

1. Sound) - The momentum 4 headphones sounded better to me, the instrument separation was very good and the sound felt detailed without feeling fatiguing or base heavy.

2. ANC) - The ANC was lacking to me; It got the job done but left me feeling disappointed at times.

3. Build and Comfortability) - super comfortable! Felt very premium.

Sony XM6

1. Sound) - good, but sort of felt like a downgrade from the momentum 4. It sounded a bit more muddy and less detailed.

2. ANC) - The anc was perfect, actually phenomenal.

3. Build and Comfortability) - SUPER COMFORTABLE! However I had issues out of the box and now im in a postion to return them as there is a strange buzzing, loud enough to travel through some songs, in the left ear.

Some questions:

1. Are there any better options for sound quality and anc

2. Are xm6 prone to build quality issues they felt fragile and having an issue out of the box left me with a not so good impression.