[Q] Disconnects from mobile network several times per day topic

Hi guys, i know this is a common problem, but i have yet to find a solution to it. My S4 (Bell Canada, KOT49H.I337MVLUFNI2, completely stock unrooted) will drop the mobile network (both voice & data), and the only way to get reconnected to Bell is by rebooting my device. After a reboot I might be good for a few hours or for a few days but it always happens again. At first the mobile signal will grey out, then eventually turn to a circle with a line through it. In the network mode setting becomes blank and non-selectable.

Suggestions around the web include selecting WCDMA only, clearing the cache, factory resets, and reflash the full firmware package with Kies3. Ive tried them all and the problem always inevitably returns.

Here are a few links to people with similar problems, but nobody seems to have a solution in any of these threads either:
https://community.sprint.com/baw/message/773419
http://forums.androidcentral.com/sam...d-network.html
https://support.t-mobile.com/thread/68518
http://thedroidguy.com/2014/02/samsu...onnected-84465
http://community.koodomobile.com/koo...ectivity_issue
https://www.youtube.com/watch?v=GlHK11pE7kA

Other than returning it for a replacement under warranty, does anybody have any other suggestions to fix this? Thanks.

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