Philips 6700 series TV

[justaguy]

Dear forumers,
 I have a Philips TV series 6700 (pn 43PUS703/12) which is giving problems. From time to time (like once per week) is showing symptoms like: slow to respond to the remote, takes ages to switch channel, loses connection to the wifi a/o the philips hue bridge, shuts down completely, apps (like prime video) freezing. Removing the power for a minute solves the issue.
To me sounds like a sw problem, like fw or cache corruption, but may have hw roots like a flash or capacitors aging. I am waiting for the symptoms to become worse and more frequent before opening it up, but in the meantime I´m asking you for some advice.
Is it maybe a known defect? Is there a service menu that allows me to perform some kind of self-test? Or a deep reset procedure? 
Thanks!