How to stop thump while the system is running?

**zots** · 11-10-2005, 01:35 PM

I have a strange problem with thump in my car. It was working flawless for a while until i took it out to replace the monitor.

Now, when i start the car and windows is coming back from hibernate, i get thump and that continues every 10 sec. Audio mute on carputer does not stop this and if i restart the car it goes away but happens during the subsequent starts (random).

I have searched here but most of the solutions address either a startup thump, shutdown thump or both but not like what i am experiencing.

I use M1ATX to remotely turn on the amp. I even turned off hibernate mode and still have the same problem. Is it possible that amp is getting turned on before PC? If that is the case, any reason why thump continues?

very annoying tup tup tup every 10 sec and no audio from PC.

The only thing that I remeber could have changed is the jumper position on SP13000 (TV out/Coaxial) when i was trying to get digital audio out of PC.

Any ideas?

Thx
zots

**Canuck** · 11-11-2005, 07:37 PM

Well, I dont have a quick fix for your problem, or any idea why you get it. But, I can suggest that you consider getting an optical amp to connect to your SP1300 (which i do believe has optical outs from the M/B). If you read this List Of 5.1/optical Amps
post you can see that some of the people posting note that they get no noise at all when using an all optical system.

So, with a 250-500 dollar investment you can not only get rid of the thump, but most likely all noise coming from the computer. (I Think).

**StrataG** · 11-11-2005, 08:18 PM

Is it consistant every 10 seconds? If it is consistant, it is likely some kind of software issue. If it is not, could it be that when reinstalling your system you didn't make a tight connection somewhere? More specifically the remote line to the amp? If it is not a good connection it is possible that you are constantly resetting the amp around turns or on bumps.

**zots** · 11-14-2005, 10:32 AM

Originally Posted by StrataG

Is it consistant every 10 seconds? If it is consistant, it is likely some kind of software issue. If it is not, could it be that when reinstalling your system you didn't make a tight connection somewhere? More specifically the remote line to the amp? If it is not a good connection it is possible that you are constantly resetting the amp around turns or on bumps.

Yes. It is every 10 secs when it happens. It starts when windows is at last 2% of completing bootup from hibernate. It also starts at the end of boot process if it is coming up from a complete shutdown. I have checked the connection an found it to be good. My remote connection to the amp from M1ATX is not that good but i am going to change that soon. Interestingly, no thump in last two days.

To Canuck: I don't have a Car amp that has optical Input. I was trying to get digital sound and use it as a HTPC box.

**pRoFiT** · 11-14-2005, 11:53 AM

I would check all Power connections. Sounds like a ground issue on the amp. Maybe turning on and then right when its about to start the overload or underload protection kicks on and the amp turns off(Thump). Then it starts all over again. Check voltage at amp during thump. Check it at the ground to constant and chassis to constant. You may have 12volts to amp but bad ground to chassis. I just had similar problem, bought a new amp and had same problem. Wiggled the ground cable and everything was good. Hope this helps