So I have the Top Fin Silentstream 10 Filter (I know not very good but I needed one quick). My other one broke earlier today, so I got another one since I couldn't find a different good HOB filter. It works great except for one thing: There is a soft noise that sounds like the impeller knocking around in there every second, it's not a linear sound, it has tiny breaks but they last no more than one second. It almost sounds like there is air and the filter is trying to prime but I'm sure it's not that. I pulled the impeller shaft out and pushed it in firm. Still makes the noise. If I turn it off for a few minutes then turn it on, still makes the noise. I know it's probably the cheap filter and it is probably fine, but it sounds like it's going to break any second, and my other one starting making this noise about a week before it broke. I have no idea what the noise is. Please help, I can't stand this and it's really stressing me out. Thank you in advance.