Mike,

Although the digital callers are better I misdoubt that your problem is caller related. Almost ANY caller will work.

I suspect that you are experiencing one of two basic problems.

1.. You might be in a poor area to call 'yotes due to hunting pressure or low population.

2.. You might not realize that playing the wind is the single most important thing to consider in hunting coyotes other than number one above. Coyotes have a nose like a bloodhound and if they've ever been hunted will approach very carefully from downwind and if they bust you will disappear without you ever knowing they were there.

$bob$

Bob, I don't those are the cause of my poor success with the cassette. In the same area, next stand, I'm able to call them in with a mouth blown call. I've switched up trying one or the other first, in the same area and I get the same results. This is on a ranch, that only I hunt (no less than 30 days between trips), so I know the yotes are there and it's not a pressure issue.
I went with my varmint mentor today (who got me started calling 20 years ago) and we used used his caller with success. Afterwards we compared the two, even exchanging the speakers. It seemed there was a little difference between the players, but very slight. The difference seemed less than the difference between two mouth blown calls that I've used succesfully.
I think I'll try it a couple more times before I give up on it and buy a digital. Thanks.