Itunes crashes when iTunes Match runs its Step 3 (not before) - any ideas why and how to fix it?

Question

Every time iTunes runs the iTunes Match, when iTunes MAtch gets to Step 3 - iTunes stops working - ie crashes. Any idea why and how to fix it? The songs are still uploaded to iCloud etc... but it crashe iTunes every single time

Answer 1

I cannot explain the failure, but I can tell you that I have a string of approx. 24 emails with Apple and a combined 10hrs of talk time with Apple customer reps that tried helping me precisely for the issue that iTunes Match would crash at Step 3 without fail. Apple even logged my Console and I was talking to an engineer that literally wrote part of the code for iTunes Match (that was the fourth and last level of customer care I was escalated to). The poor man almost quite his job, and I just about demanded a refund for my $25, since iTunes Match simply wasn't working.
Then I studied at a friend's place, and I noticed that all of a sudden, while iTunes was running in the background, half my library was already uploaded and things were progressing smoothly. It turns out that it had something to do with my modem specifically, as I had already hooked up my computer straight to the modem, taking the router (TimeCapsule) out of the equation. Nothing worked. Firewalls were turned off, no AntiVirus existed, and Apple engineers tried everything possible, incl. remote access on my computer, to get this to work. Nothing worked as long as I was connected to a Motorola Surboard.
At every other network, wether at Starbucks, my university, or at friends places, however, iTunes Match worked flawlessly.
After some research online, it turnes out that a handful of people with Motorola Surrboard Xtreme cable modems had similar issues. Eversince, I simply use my neighbors wifi should I need to upload songs, and I have no issues. Oddly enough, matching (not uploading) works just fine with my Motorola.
Don't ask me how or why, I am interested in computers and work with them a lot, but I am no engineer. I can tell you that simple scientific method pinpointed to the modem, and I haven't had issues since then.