Download product problems - Download Streaming vs. Redirect

The short problem is that my store contains a mix of downloadable products (mostly zip and pdf files) as well as restricted access page products. Currently, the site is set up as Download by Redirect - and that worked swimmingly on my previous host for all products. We switched hosts about a month ago and now about 30% of customer's downloads get cut off prematurely (usually within the first 500k) with a successful "Download Completed" message (the download is neither successful nor complete and the files therefore do not open). Restricted access pages work fine, however.

To remedy the "downloads being cut off" problem I tried setting the site to "Download by streaming"... however this flat-out breaks the restricted access page products as the browser attempts to *download *the html files instead of navigating there.

So currently I'm stuck as if I leave ZC on "download by redirect" an unacceptably large number of users experience download problems... but if I set ZC to "download by streaming", the restricted access page products don't work at all.

So does anyone have any ideas about why the downloads may be getting cut off when ZC is set to "download by redirect" and how I can ensure this doesn't happen (without using "download by streaming", which doesn't work with restricted access pages)? Possibly a php.ini setting needs to be tweaked? I'm at a loss here.

You might ask your host what their php time out settings are...
Or if you can generate and use a local php.ini file to change this

other people including myself have found that turning "Gzip compression" off helps with download issues. You can find it under
"Configuration-Gzip compression".

Unfortunately, GZip is already disabled... so that doesn't seem to be the problem. :(