Right… If you don’t need to monitor a backing-track from the computer, plug your headphones into the Edirol. Or, does the Edirol allow you to monitor a backing track while recording (without a computer)?
There are interfaces (or USB mixers) that allow zero-latency direct-hardware monitoring while you also monitor a backing-track from the computer. IMO - This is the best solution.
I thought this was like a latency issue,
Yes. “Latency” = “delay”. There is always some latency through the computer. There are ways to minimize latency and it can often be reduced to the point where it’s not noticeable, but the best solution is to avoid monitoring through the computer.
I’m using an RCA to mini jack out, straight into the front port of my PC. Now after a bit of messing around I can get audacity to recognize this as a Mic and it allows me to record.
Is that a line-input? (A mic input won’t give you good quality.) Since you have a digital recorder, typically you’d transfer digital files to the computer (if you want to use the computer for post-production editing or mixing, etc.).
There is a free online book about optimizing your computer for audio called [u]Glitch Free[/u]. Pros (and semi-pros) use hardware and software that supports ASIO drivers which are designed for low-latency (when they are monitoring through the computer). Audacity doesn’t support ASIO, and with ASIO you may still have to optimize your computer.
Anything I’ve seen is blaming the interface/DAW setup or whatever, but seeing as I don’t have one
Your “interface” is your soundcard and your “DAW” application is Audacity. (I classify Audacity as an “audio editor”. Full DAWs are generally designed for multitrack recording & mixing, and they support MIDI.)
Latency is the result of buffers which are required with a multitasking operating system. (Your operating system is always multitasking even if you’re running only one application.) Buffers are like holding tanks - When you record, the audio flows into the recording buffer at a smooth-constant rate. When the operating system gets-around to it, the buffer is read and the data is sent to your hard drive in a quick burst. If some application, driver, or background task “hogs” the system for a few milliseconds too long and the buffer doesn’t get read in-time you get buffer overflow and a dropout/glitch. There is also a playback-monitoring buffer. It works the opposite way… It gets written-to in a quick burst and the audio data flows-out at a smooth-constant rate. The danger here is with buffer underflow.
Bigger buffers mean more delay but less chance of a glitch. A faster computer also helps, mostly because it can finish-up the background tasks faster.