Hopefully someone can help me on this.
 
I have a SE220A condenser microphone plugged into my Edirol UA-25 audio interface, I'm using Home Studio 8.
 
I can record, no problem when the Input Echo button is off. However, when it's on I get weird noises from it. When I record with the Input Echo button, the noises are not recorded as well.
 
Any help would be really appreciated.
 
 

Normally we don't have the input echo on at all when recording Audio. Only MIDI. Having it on will possibly cause you to hear latency. Very few systems are good enough to have low enough latency to allow the use of monitoring "after" the signal has passed though all that stuff. It is best to monitor at your intrface using what we call direct monitoring. Your hearing the real time analog signal of your mike before it is converted to digital etc. The playback of Sonar is correctly adjusted so that all is in sync.
My guess is the "weird noise" your hearing is possibly a loop back issue.
Anyhow this is not a problem, just don't turn it on.
 
If your Edrol has a software mixer you might want to check the routing.

I used a UA-25 for awhile, and that thing generated a lot of noise that seemed to be coming from the USB port. At least, the noise would stop completely when the cable was disconnected. I bought a higher-quality USB cable, it didn't make any difference. I wrapped the USB cable in aluminum foil and grounded it. No difference. I suspect there is a design flaw in the interface.
 
Recently, I dug the Edirol out of the junk box after my MOTU died, and was shocked at how noisy it was. Right back into the junk box it went!

Sorry I should have asked if your interface was bus powered, I usually do. see this thread, same issue.. 
http://forum.cakewalk.com/Intermittent-squealing-from-Speakers-m3043746.aspx
 
I personally never recommend bus powered interfaces because this issue is common among them. My M audio Fast track was tossed for this reason..

Thanks for all your advice guys, I've sorted it.
 
On the Audio settings I changed the Driver Mode to ASIO and on the Audio Bit Driver I changed it to 24 bits. This has got rid of the noise.
 
I was using the WDM/KS at 16 bits previously.
 
All sorted now, thanks again.