Quoted from Yokimato:One thing I did notice while putting on my topper was that the sound bar is sending out some "noise" when idle on. You can't hear it when the game is running, and you'd have to be close to the sound bar to hear it, but curious if this is common?
I didn't skim through all of the pages of the thread to check for others that responded to your question, but I figured I would share my audio issues from my new table delivered yesterday (September manufacture date). I also opened a new ticket last night with API in case anyone from API sees this before the case response goes out.
As I played first game after setup, a static hiss and ticking sound steadily grew louder as the game audio faded. The distributor's delivery guy and I shut off the table, pulled the backglass, and noticed a few of the speaker wires in the amp were loose. We reseated the speaker wires which stopped the behavior, so we chalked it up to the table's ride to my house jostling things loose. I still had a faint buzz, but I could at least hear the game audio consistently.
During my bout with insomnia last night, I poked around a little more to find the buzz and I found something to explore. There is a 3.5mm cable connection between the P-ROC (PC?) audio out and the amp driving the speakers. The buzz sounded like ground loop feedback, although the cable goes through a ground loop isolator. I messed with the 3.5mm cable at all of the cable plug junctions (wiggling and partial plug pulls) which caused the same noise to come back, so I continued to dig.
As soon as I fully disconnected the 3.5mm line the buzz went away, so this looks like this may be a problem with noise on the audio feed or a true ground loop problem since there is a powered amp involved. I unwrapped the audio wires from the two holding clips, and the first thing I noticed is that I believe the isolator was connected in reverse. The "Out" side of the isolator was plugged into the main audio output port like this:
P-ROC (PC?) case audio out (F) > (M) 3.5mm stub cable (M) > (F) "Out" label side [isolator] "In" label side (M) > (F) Amp 3.5mm input
After swapping the connections, the buzz went away and the noise is now reduced to a ticking sound. I also tried using the stub cable to go straight from the P-ROC into the amp to see how bad the noise problem is without any ground isolation. Don't do it, horrendous feedback and noise.
Next step, I'm going to look into a new ground loop isolator replacement in case this isolator is faulty. Possibly something like this one that has a ground shunt, direct 3.5mm support to avoid adapters, and won't cause low frequency (bass) attenuation:
https://www.bestbuy.com/site/metra-ground-loop-isolator-black/9855136.p?skuId=9855136
I might look at adding a clip-on ferrite bead on the cable, but this may be a relatively cheap fix if it works. I might take a look at upgrading the speaker wire to stranded copper core, but hopefully I can avoid that invasive of a change if it isn't needed.