WRONG URLS in generated <script> tags

I've found a strange issue which can't be systematically replicate, seems a threading problem.
Fragments of JavaScript are appended to a request controlled by cassette!
This generates a server error (http code 400) caused by invalid characters in url.
Don't know if it comes from cassette or it's a browser problem...
We replicated it only once using Chrome 16.0.912.75
The strange thing is that the "show page source" browser command reveals a well-rendered tag.
But, where do these requests come from??
The JS SEGMENTS appended to the wrong URLS are present in the response of the right request
/_cassette/scriptbundle/Scripts/Bundles/jQuery_1ca926269980eb00875d1d5e2c51a3458d0d2058

these are some wrong requests (taken from IIS log)

GET, /_cassette/scriptbundle/Scripts/Bundles/jQuery_1ca926269980eb00875d1d5e2c51a3458d0d2058/)&&r.html(i)):(r=n(, -,
GET, /_cassette/scriptbundle/Scripts/Bundles/jQuery_1ca926269980eb00875d1d5e2c51a3458d0d2058/)&&f.html(o i( 80
GET /_cassette/scriptbundle/Scripts/Bundles/jQuery_1ca926269980eb00875d1d5e2c51a3458d0d2058/]};u.optgroup=u.option,u.tbody=u.tfoot=u.colgroup=u.caption=u.thead,u.th=u.td,i.support.htmlSerialize||(u._default=[1,