I’ll say use Hybrid, it’s more powerful and you seem to execute it. Masked is the weakest format and judging by your report it seems to be indeed too weak to get you results. Why stick with a format that does not seem to be working for you?
You do not need to set speakers on either side, it’s slightly more effective but not by much. You can use one wired speaker or even the phone speaker, that’s what Shannon does. You’d have to double check the quality of the phone speaker obviously, but many people do it and it works very well.
As for the six hours listening time, if you use your phone you can carry it around with you when you leave the room, ez.
And consider yourself lucky it’s just 6 hours, I am now listening for 9 hours and 20 minutes 
Edit: if Hybrid is too much you can use ultrasonic, that’s in between Masked and Hybrid in power. Ultrasonic is generally the recommended format for starting.
You do not need to set speakers on either side, it’s slightly more effective but not by much. You can use one wired speaker or even the phone speaker, that’s what Shannon does. You’d have to double check the quality of the phone speaker obviously, but many people do it and it works very well.
As for the six hours listening time, if you use your phone you can carry it around with you when you leave the room, ez.
And consider yourself lucky it’s just 6 hours, I am now listening for 9 hours and 20 minutes Edit: if Hybrid is too much you can use ultrasonic, that’s in between Masked and Hybrid in power. Ultrasonic is generally the recommended format for starting.
