We send email from our main domain "vocalsound.org". It is delivered through our hosting provider, which however sends it through a shared mailserver hosted on their generic domain (webland.ch).
This is getting to be a problem, since "From and EnvelopeFrom 2nd level mail domains are different", as for example SpamAssasin notes:
Some recipents such as gmail do not have a problem with this, they will simply mark the mail with a "sent through" / "via" note, such as: "firstname.lastname@example.org via webland.ch".
Other mail servers (such as: laposte.net, free.fr, register.it) however will flag the email as SPAM, independently of its content, or even refuse to connect: "560 5.7.1 Service Service refused. LPN007_510". Or in some cases, they even pretend to deliver the email (the smtp connection is successful) but the email will never reach its intended recipient, not even as spam.
This is a huge problem not only for newsletters, but even for our daily correspondence: in order to keep in touch with some contacts, we had to open a gmail account because otherwise they will not receive our email.
Some years ago, we had our hosting at another provider, but never encountered this issue, since our mails resulted to be sent directly from our domain.
1) Can this be considered a "bad practice" or even "misconfiguration" by our hosting provider, or is this usual practice on shared hosting?
2) To resolve the issue, should we consider changing hosting provider?