Sm58 feedback issues

You have to start outside.
First regrade slope of soil away from foundation. Add a drain and tile to direct water away from house.
If necessary dig down along foundation wall and add membrane.
In the basement, add a sump pump to pump out water to keep moisture out.
Clean basement wall, and add some waterproofing paint.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Go to Home Depot, Rona or to any hardware store, and they will show you different staff to repair the cracks.Very economical.

Proper placement of mics versus the speakers of a PAS is important to avoid feedback. Your speakers need to be toward the audience from where the mic is. If the mic can "hear" the speakers you will likely have feedback. The mic should work even though it is a consumer grade mic.
WORD OF CAUTION: There are a LOT of fake SM58 microphones being sold... even on Ebay... SOME are fairly high quality and others are not.

What is in the room above the basement bathroom?
And how large is the diameter of the vent pipe you need to run?
Do you have a maximum number of elbows, and runs of feet maximum you can't exceed?

Is the Frame wall above the foundation, accessible by going up thru the ceiling of the bathroom, and the elbowing over and into the outrside frame wall at that point?-- and then up a ways, and then out thru the outside wall?

Another possibility would be: How far to a window, or vent already in the basement?-- Could you run the piping there, and then out?

How thick is the concrete wall?-- Is it reinforced Concrete-- or just Masonry Block wall? A block wall is not as hard to get thru--

I know I asked a lot of questions-- but maybe it helps you think thru your options?

Le4t me know if I can help further.

Mack B

Other than being dropped, or the xlr connection is faulty...a sm58 is pretty indestructible. Try a differnt cable, a different channel on the mixer. Mght be time to spend the 100.00 and get a new one. Be careful of fakes that are out there.

thats normall it just lets of presure when needed which will cause a little water

It sounds as though you are pointing the peavey at the band in a practice situation? If so make sure that each speaker is at about 60 degree angle to either side of the back of the mike (you facing the speakers), most mics reject feedback when the the user is directly in front of a monitor, but Beta 58s' tend to feedback more in that situation. Alternatively (if it is a practice room situation), why not place the speakers behind the band at 60 degrees each and turn to face the band.

That is a great mic. It has a lot to do with the room your in and acoustics of it. If you are too close to your PA or monitor, it will also feedback. Lowering treble and reverb will also help.