mme is the worst for latency.
you might want to try switching it to wmd and see if that gives you better results.
because with using mme im surprised you got it to work without this problem before.
reltek soundcards are the worst for digital audio recording.
let me re phrase it..the bottom of the barrel soundcard.
they are great for watchingyou tube and listening to mps on laptop/desktop speakers but not for digital recording man.
im going to forget you said this was working good before and start over here
if you want to eleveate this problem and fix it rightnow,then do this.:
download the dpc latency checker.
http://www.thesycon.de/deu/latency_check.shtml this small tool installs in seconds and will tell you if your system is able to support digital audio.
run it for about 2-3 minutes while using sonar and your keyboard.
if you start to see the bars in the red then your system is not capable of digiatl audio recording without latency.in other words..your bumbing out.
if this is the case then you will need either a new soundcard that will support it(i suggest just asking around here or doing a search,believe it or not,cakewalk makes a few really nice ones for about 100.00 to 400.00 depending on your buget and seriousness
for now you can get away with downloading a program called "asio4all"
http://www.asio4all.com/ make sure you read the 5 page manual good so you know how to set it up properly.
by using this asio driver you will be up and recording in about 10 minutes if you set it up correctly and will never here this delay thing ever again.
it is my suggestion that you go this route,why?
because your only using a keyboard and a usb addapter to do your recording right?
when it comes time you want to add vocals/guitars/drums/..then look in to a good audio interface.
we were all at the point you were once apon a time,matter of fact what brought me to thins forum was the same thing your asking right now.
and someone was pleasent enough to explain this to me as im doing to you with the promice i would help someone else out someday.
well ive helped many out now so consider yourself one in a long list.
learn about asio4 all in the manual and your problems will be solved..trust me.i did it untill i upgraded to many different devices now.and im happy to say i use a cakewalk v studio 20..it has all the faders on it so i can use them to control the faders in soanr,i also use an m audio oxygen 49 keyboard to control another 8 faders/pan knobs.
its also a good keyboard.
both downloads are virus free,sure check them,but dont worry,no freeware virus or bloat attatched.
do what i told you and report back in a little while.
ill try and check back in an hour or two to see how your making out.
charlie roy