I doubt we have many around here that have answers to such a question offhand, even on consoles we commonly consider and play component level fixing on.
For it to suddenly happen and be cured in that way usually means a component in there has failed -- capacitor dried up, filter broke, inductor coil failed/shorted, one of the previous bypassed as someone spilled something... or maybe that the laser is on the way out and whatever auto correction it does pumped the power and with it came the noise. The other option is it is acting as an antenna for some other noisy device (take it to another room/house, put it in the middle of the floor rather than the TV cabinet, maybe do some shielding) but that is unlikely for a CD drive.
Solutions at this point are one of three
1) You track down the failed component, assuming it is that, and replace. I don't know what the Saturn peeps are up to these days as far as diagrams, hope you don't have to get a matching one and compare values. Might be enough to probe with an oscilloscope though. Could also scrounge maybe a whole drive assembly from another Saturn, though that could be an expensive hobby (I don't think they were tied to a system, though I also don't know how many models of drive there were and their mutual compatibility).
Could also be if you bolted some other device on there that also draws power that a capacitor, resistor or something that would have chugged along for years under stock conditions is suddenly being forced to do work and has failed accordingly. In that case upgrades or alternative points for power might be the order of the day.
2) You isolate the noise either at the CD level or the A/V out level (filters, capacitors, whatever does the trick).
3) You cut down your drive to be the minimum viable product for the I presume that Satiator is a mod chip or drive emulator.
If life is nice it will merely be that the Satiator measures a resistance and you then chuck a resistor across the thing (see things like airbags in cars and screen detection for those making a single screen DS to play GBA games or have a swap screen button and do DS games).
As I am not going to predict life being that nice you may then need to figure out what you can lose from the drive and still have it behave suitably for the Satiator whilst also curing your noise issue (you can bring in elements of 1 and 2 here as well). Normal sources of noise are motors and optical drives tend to feature those to disconnect (maybe need to chuck a resistor across it) and also figure out any detection methods you might also need to bypass here (see things like how to fake out a car CD player such that the line in works for it but probably a bit more advanced).
Have fun.
