The song sounds very nice overall but there are some problems, particularly with the triangle channel. Since all your DPCM samples end with a high delta-counter this makes the triangle a lot quieter and it's very hard to hear. To fix this, go to the DPCM tab, select a sample, go to "edit" and then select the last part of the sample and press the "tilt" button until it ends with a higher delta counter, then repeat this with all of them. This will make the triangle a little louder.
Also, as a suggestion, sometimes you can apply a slight vibrato when you have a note that lasts for too long, so it doesn't sound so plain.
If there's anything else you could apply to the rest of the channels it would be nice because there are some spots where the song sounds empty. Still, this sounds very good.
