I've been trying to teach myself Spanish with a couple of computer based training programs. The first program I tried, Transparent Spanish. This program has been pretty good for helping me build reading a vocabulary. But I had a very difficult time listening to the recorded speech. The parts of the program devoted to helping you develop listening and speaking skills lack instruction.
This second program, Pronounce It Perfectly explained why I had difficulty discerning words while listening. Apparently in Spanish not every syllable is pronounced. If a word ends in a vowel and the following word starts with the same vowel, the words are run together and only one syllable is pronounced. Sure that makes pronunciation easier, but that makes it much harder for people like me to develop listening skills.
My one complaint with Pronounce It Perfectly, is the timing. After listening to a phrase, the program asks you to repeat it. But half the time, the program doesn't give you enough time to say the whole phrase before it moves to the next one.
I wouldn't recommend relying solely on either of these programs. But both have their strengths and weaknesses. Using them together I'm building at least a little skill.
Update Feb 2023: Neither of the programs mentioned above held my attention very long. In Aug 2022 I started using duolingo, and that has held my attention longer than any other language learning program.