Kind of upset, did I make a mistake in purchase?

[- sam -]

Long story short I've owned this headset for 3-4 years. I love it so much. -
https://www.amazon.co.uk/Sennheiser-PC363D-Surround-Over-Ear-Headset-Black/dp/B008O515CK

The problem is they are very worn so I ended up buying a new pair of headphones. I decided to go with these because I don't need a microphone.
I bought these -
https://www.amazon.co.uk/Sennheiser-HD-599-Around-Ear-Headphones-Ivory-Matte-Finish/dp/B01L1IICR2/ref=sr_1_1?s=electronics&ie=UTF8&qid=1511558874&sr=1-1&keywords=hd+599

The reason why I am sad is because my old pair had volume control on the side whereas these new headphones don't. Also if I don't use the 7.1 surround sound adapter from my old headset with my new headphones the headphones sound terrible for some reason.

I think I made a mistake. Do you think I should of went with an upgraded version of my old headset?

Basically what I'm asking is which one would you pick out of these.

1) https://www.amazon.co.uk/dp/B01IBORI2O/ref=sspa_dk_detail_0?psc=1
or
2)https://www.amazon.co.uk/Sennheiser-HD-599-Around-Ear-Headphones-Ivory-Matte-Finish/dp/B01L1IICR2/ref=sr_1_1?s=electronics&ie=UTF8&qid=1511558994&sr=1-1&keywords=Sennheiser+HD+599

 

[Ralston18]

Could be that you have mismatched the plug types.

Google "TR TRS TRRS" (Tip, Ring Sleeve)

Here is a good starter link to explain things:

https://www.provideocoalition.com/ts-trs-trrs-trrrs-combating-the-misconnection-epidemic/

The 559's appear to be TRRS.

Verify the connections in use. If there is a mismatch there may be an adapter to correct.. I.e., the 7.1 surround sound adapter that you mentioned or some variation to restore the correct/required connectivity between headset and audio source.