I usually don't listen to music when I'm designing levels, but I listen to it when I draw graphics, mostly Chiptune (She, I Fight Dragons, Toriena...) and Heavy Metal (Macinae Supremacy, Crow's Claw, Master Boot Records...).
I also like some Crush 40 songs as some people here (the Sonic band), Fire Flower is my favorite song by this guys, I discovered The Cult (other heavy metal band) because of it.
When optimizing my texts, I either watch some videos on the Internet (Vinesauce videos especially since they are very long and enjoyable, which is the perfect thing that I need when working on these MMLs), watch some anime (I watch both of those with Notepad++ on the (usually) right side btw, before anyone asks), or listen to some VGM/chiptune, both VGM covers and original songs entirely, mostly from fairly obscure chiptune artists because why not (heck, I'm even listening to some rn LOL)
Honestly, I can't put myself to listen to podcasts and such while rom hacking without getting distracted and slowing down the process like others seem to do, so I stick to Ninty games OSTs and Famitracker covers. In fact, I have a fond memory making a christmas-like level around december last year and getting like, a super inspiration boost by this for some reason. Good chiptune can really pump the hell out of my brain.
NEW GAME OP 10 HOURS
SONIC FORCES FIST BUMP
HIMOUTO UMARU-CHAN OP
HIMOUTO UMARU-CHAN R OP
CURB YOUR ENTHUSIASM THEME
SOME MUSIC BY ȘTEFAN BĂNICĂ JR
THE GARFIELD SHOW INTRO
TOTALLY SPIES INTRO
JUMP UP SUPER STAR
PMTTYD BATTLE THEME
SONIC CD INTRO
Anything, really. I usually shuffle Youtube channels for major artists/bands that I'm marathoning for whatever reason, usually because of them trending at the moment (or in the case of a big one recently dying, i.e. Avicii or XXX). Other times I boot up the good ol' VGM folder and play that as well.
Though lately in the past couple years I've also been listening to a lot of SilvaGunner since a lot of those remixes are unironically fantastic (Death by Lucky Strike, Dr. Soulja, and Wood Man US version are all great examples).
It depends on my mood, but I usually like to put some random metal or hard rock album that I can sink in and let time fly.
Recently I'm listening to remixed versions of Mega Man and Mega Man X's songs or seeing RedLetterMedia's videos on my phone, they're pretty long so they fit with hacking, especially kaizo, considering I hack for like 7-8 hours straight (coming up with ideias and testing them out).
-------------------- Listening to metal, loudly.
I pretty much always listen to some form of video game music, often related to the level theme but not always (sometimes I just want something upbeat, or calm, or whatever). I find that I can't enjoy music with lyrics as much when my attention is focused on something else.