[22:00] <holstein> zequence: im not an electornics expert
[22:00] <holstein> so we dont have to talke about taht in the main channel
[22:00] <holstein> zequence: i dont care
[22:00] <holstein> im just saying, i ge more noise at lower latency
[22:00] <holstein> why? im assuming something is doing more at lower latency
[22:01] <holstein> is it power?
[22:01] <holstein> i dont know/care
[22:01] <holstein> hypothesise away, but i assue you im not tyring to be "correct"
[22:01] <holstein> im just stating what i have seen 
[22:01] <zequence> I'm not making any claims that are "hypothetical"
[22:02] <zequence> Just narrowing down what could and what could not be the cause
[22:02] <holstein> sure
[22:02] <zequence> I'm only interested in solving the problem
[22:04] <zequence> I've sometimes experienced that a screen can cause noise to audio devices. The whiter the color, the more noise
[22:04] <zequence> And it has happened that a hard drives activity has leaked into the audio signal as well
[22:05] <zequence> In both cases I would think it's some sort of ground problem
[22:05] <holstein> yup
[22:05] <holstein> i would hypothesise a power issue there as well
[22:07] <zequence> If the CPU activity is audible, then it kind of sounds like the same thing. I was jusr surprised that low latency would be that audible, as it's not really that much more CPU intensive. If it is a ground problem in this case, it would make sense that anything CPU intensive, at any latency would give noise
[22:07] <zequence> Just that there might be more noise at lower latencies when the PC is idle
[22:08] <holstein> i dont think its cpu activity
[22:08] <holstein> its a constant noise
[22:08] <holstein> you start jack at that latency, and its pretty steady
[22:08] <holstein> i high pitch whine
[22:08] <holstein> its odd
[22:09] <holstein> i solved it much the same way though.. by looking into grounding
[22:09] <len-1304> holstein, The PS for the FW unit may be a switcher.
[22:09] <zequence> holstein: You said that the noise increased in volume at lower latencies. Does the pitch change too?
[22:10] <holstein> zequence: i dont remeber that.. but i dont think so
[22:10] <holstein> i think it ws the same pitch and louder
[22:11] <len-1304> Sounds like the power supply
[22:11] <len-1304>  Small switching power supplies have gotten cheaper... I see them even in wall warts
[22:12] <zequence> It's just that I don't see how the latency would affect the FW power supply
[22:12] <holstein> if it causes the device to pull more power
[22:12] <holstein> *if*
[22:12] <len-1304> If it is an old unit, I would think the caps are drying out.
[22:12] <zequence> But, how would it do that? It's a constant stream of data, no matter which latency
[22:13] <len-1304> The FW unit fills a buffer and sends it every so often, low latency means the cpu in the FW unit has to deal with that part of things more often
[22:14] <zequence> len-1304: Isn't that done in the CPU?
[22:14] <zequence> the buffering, I mean
[22:15] <holstein> zequence: i think you are assuming a constant stream of data.. maybe its not constant?
[22:15] <holstein> in not sure
[22:15] <zequence> It is a constant stream, but it's also buffered
[22:16] <zequence> lower latencies means smaller buffer sizes
[22:17] <zequence> I'm just assuming the buffering is done in the CPU, and not in the audio device.
[22:24] <zequence> AFAIK, an audio device sends and receives one sample at a time, following the clock
[22:24] <holstein> i wish i knew more about it
[22:25] <zequence> If you increase samplerate, the rate at which samples are sent/received increases
[22:44] <len-1304> zequence, (just had lunch) the FW unit also buffers (as does the ice1712) and sends a bufferfull of data at a time. The driver tells the IF how big the buffers are that it wants.
[22:44] <len-1304> That is why there is a lower limit to buffer size for any IF.
[22:46] <zequence> len-1304: How about a higher limit?
[22:46] <zequence> While jack has a limit of 4096, OSS can go higher
[22:47] <zequence> But perhaps the sound server makes up for it
[22:47] <len-1304> That would be a jack limit then.
[22:47] <zequence> I wouldn't expect audio devices to be limitless anyway
[22:47] <len-1304> The bigger the buffer used the more shared memory must be set aside
[22:49] <len-1304> But I have three audio interfaces, the lower limit on each is different (-p128, -p64, and -p32) Jack will not even start if I try to use less... because jack tells alsa to ask the device to set a smaller buffer size than it can and the device refuses (sends an error back)