Hellzero

If you read the OP, you'll find your answers @RhythmJunky...

I'm back on piano for good and working grade 5 to 7 pieces, but I've lost some independence, timing and sight reading, but music theory is well anchored in my brain. I'm taking lessons again, with a private teacher, but way cooler than before and yes it's very hard, but I'll hang on... Slowly, but surely. Take your time, and all will become clear and evident @bass_dinger. 😉

I guess you mean the HeadRush Gigboard or MX5, why not moving to the newer versions named Core or Flex Prime or even the Prime, but it's a huge beast. I'm using the Core and I really like it, easy to use with its wide touchscreen, and the tuner is very visible. Check Nate Navarro's video of the Flex Prime... Ok, this guy could make an air dryer sound like an Alembic on steroids.

First question to ask as the pickups are single coils: Is the bass fully and correctly shielded?

This reminds of a quite similar situation: I went to buy (only 250 kilometres round trip, but twice, read below for the funny part) an Ashdown CTM-300 with its dedicated made in U.K. 8x10 cab, and came back with an Ashdown CTM-100 with an Ashdown 1200 Watts made in U.K. 4x10 cab as I own a stupid Peugeot 508 with a trunk and not a hatchback, so I had to put the cab on the back seat as it couldn't get in the immense trunk and the head in the said trunk. That said, eventually, the 100 Watts head coupled to that 4x10 cab was more suited to my taste, so a win-win situation. Now, the funny part: I had to go back there the next day has I had forgotten my jacket with my wallet at the seller's place and only noticed it when back home, you know the "new toy syndrome". 🤦🏻🤪🫨 My wife who accompanied me both times was laughing like a child and I had to pay the restaurant on the second day. 😉

AI (de)generated description with a stupid "rich rosewood fretboard", when it's maple... It's not a Fender at all as everything is fake including the logo, maybe not even worth the starting price. Run away.

I'm in Belgium too but not close to Brussels as I live in the South in Gaume (Étalle) otherwise I would have proposed you to have a look at the bass as I used to have my own luthiery and repair shop. That said, the transfer of a warranty to a second owner is not a legal thing as the warranty is accorded to the first owner only, that's the law over here in the E.U. That said, there are few exceptions like car makers who accept this transfer, or some big suppliers, like Thomann, who accept this for some items, often expensive to very expensive ones. To prove a flaw in the design, you'll need to have the said flaw confirmed by an an expert to be legal, which will cost you more than the pickup(s) swapping. As it's a trade between private persons, there is absolutely no legal warranty, and having bought it wouldn't change a single thing: no legal warranty. Furthermore, if you have tried the bass before accepting the trade, you have absolutely no right to ask for any kind of partial refund, as you have done it accepting that the state (condition, if you prefer) of the said instrument is as is and known by the "buyer". There is always a solution to a problem, but here you're walking on thin ice, so better be diplomatic with the maker as you'll also have to prove that the bass wasn't modified. As others said, giving the brand name and model with a photo "describing" the flaw would help a lot.

Check if simply unplugging the router from the mains and also anything WiFi stop the noise. To put it simple, these are extraordinary mains polluter.

And if there are too many pigeons, just remember that The Chase Is Better Than The Catch.

Are you playing nearby a router or anything WiFi?

Or, to quote, without freezing the progression chord by chord...

I think @The Guitar Weasel is some kind of a luthier. 😉

Do you need glasses, coffee, grammar, smaller fingers or the whole package, Russ?

My shrink says I have to write all these awful memories to be at peace with myself and then burn them, but I still haven't clearly understood if I have to burn you... 🤔 🤪

And you also took a bus to Brussels to meet me for a trade. 😉

You can wipe them with some alcohol before fitting them as you will remove a lot of the remainings of the polishing process, and don't forget that you'll have to readjust the intonation (a lot). And as usual with all strings, bend them at 90° or more before cutting them and fitting them. 😉

This guy can't play, that's awful! 🤢🤮

Hmmm, hmmm.

Also check if the nut is not too low...

I'm a pure CBS child. And my wife is a pure moon child (not sure who will understand this one).

Pre-CBS? 🤦🏻🤔😂🫨🤪