Garageband Symphony Orchestra Jam Pack

Hello, my Mac arrived yesterday and I'm new to GarageBand which may mean I'm simply having a blonde-moment and have just missed something.
But otherwise, some of my software instruments don't work.
I have GarageBand and the Symphony Orchestra Jam Pack installed. What will happen is that I'll create a new track, select one of the brass or woodwind instruments, and open the 'musical typing' window where I can play the notes. The problem is that when I play them, there is no sound. I'm tapping the keys and no sound is coming out. If I select a different instrument such as the grand piano, it works fine. It's only SOME of the Symphony Orchestra instruments (and the instruments which don't work change as well. I.e. - one minute the horns arent working, and the next minute they're fine and the woodwind instruments aren't).
Other than this the system/software runs perfectly.
I've taken some shots of something I've noticed that's different between the instruments that do and don't work. See below a picture of the details box which comes up to the bottom-right of your screen when you select an instrument (that is working!);
http://i23.photobucket.com/albums/b386/Ourumov/DSC00146.jpg
But this is what comes up for the instruments that aren't working;
http://i23.photobucket.com/albums/b386/Ourumov/DSC00144.jpg
Notice that under 'Instrument Generator' it says 'None', whereas in the first picture it had details. Also the drop down menu doesn't contain anything useful, and the colours have all changed to grey.
Any help would be much appreciated, as the Apple forums haven't been much use thus far!
Operating system;
Mac
Mac OS X (10.4.10)
2.8 MHz / 2GB RAM / 750GB Memory

Each Jam Pack offers thousands of Apple Loops and software instruments.

Garageband symphony orchestra jam pack freeGarageband Symphony Orchestra Jam Pack
Editor: Each Jam Pack offers thousands of Apple Loops and dozens of playable software instruments. Jam Packs can also be used in Logic Express 7, Logic Pro 7, and Soundtrack Pro, offering novice and professional musicians alike a wide assortment of new sounds to stretch their musical creativity.
Rhythm section:
If you’re looking for a backing band, Rhythm Section provides a veritable drum construction kit. Assemble a solid foundation of drums with varied sets of fills, grooves, and groove variations. Thanks to the wide variety of drum sounds available, you can create human-sounding performances. Rhythm Section also provides dozens of playable instruments: ten strings, ten basses, and ten drum kits.
Remix tools:
Gotta groove? This Jam Pack’s for you. Designed for electronic dance music enthusiasts who like to move to Hip-Hop, Techno, Trance, and R&B, Remix Tools offers beat kits, sound effects, synth sounds, and the rhythms of classic Roland drum machines.
World music:
Let your musical wanderings take you to more exotic places with World Music. Recorded over the course of a worldwide expedition and featuring an unprecedented collection of world loops, ethnic percussion, exotic strings, and regional wood instruments, World Music captures the most AUTHENTIC performances in dozens of Countries, genres, and playing styles.
Symphony Orchestra:
Symphony Orchestra lets you conduct a full orchestra, from Brass and percussion to strings and woodwinds. Create classical compositions or soundtracks, or add the power of a symphony to your GarageBand pop, rock, and hip-hop songs.
Fixed some bugs.

Garageband Symphony Orchestra Jam Pack. Tap a numbered badge in the Sound browser, Template browser, Loop Browser, or anywhere you can choose instrument sounds. Download a sound pack In the Sound Library, tap the sound pack you want to download. Discuss: GarageBand Jam Pack 4: Symphony Orchestra - media Sign in to comment. Be respectful, keep it civil and stay on topic. We delete comments that violate our policy, which we encourage you to.

1.0.1
03.09.10
Free
English

Garageband Symphony Orchestra Jam Pack Free

413KB
Mac OS X
Truly authentic solo and accompaniment guitar parts.
Mix tracks intuitively, play with effects, loops, or scratch.
Garageband symphony orchestra jam pack torrentPack

Instruments Symphony Orchestra

Mix digital music or video, replacing your turntables and CD players.

Symphony Orchestra Mp3

Create drum or audio loops and play sample files and MIDI instruments.