Pod HD Pro X, Help

[StaffK]

I 1st started with line 6 Over a decade ago with the XT Live Running through a Randall RH100 head with Marshall JCM800 Lead cab. The rig was loud. I bought the HD500 a couple of years ago and ran it through the RH100 Head & RH100 G2 Heads through Marshall 4x12 again sounded good apart from a bit of digital hiss. I upgraded to the Pod HD Pro X last year and that,s when the problems started. I was advised to buy a power amp to eliminate Pre-amp to Pre-amp interference so that,s what I did. Sold the Randalls (Big Mistake) was told the best to buy was the Rocktron Velocity 300 which it isnt a bad rig apart from theres no guts in it when running the Pro X & there,s a lot of low volume tones which really need boosting. I was going to sell the power amp and buy 2 matching amp heads & cabs to get the sound back I used to have but before I thought I,d run a test. Tonight I ran the old XT Live through the rocktron and had to turn everything down.  So the Problem is the Pro X is so Quiet so on the back of the XT theres a line/amp switch with a rear volume pin, is there something like this on the Pro X that i`m missing.

 I`ve played with the Destination settings wasnt too keen on the studio setting so ran it back to front power amp. So is there a rack booster I can buy to sit between the Power amp & the Pro X. I was going to ask If anyone had any Ideas for best suitable power amp or amp head but more so Whats the best Cab combo out there. I would eventually move upto the Helix but its a long way off. I need to sort the output source 1st. So any advice would be helpful..

Cheers

[StaffK]

Thanks for that Guru. I know about the Line level. I`ll try the EQ at the end of the chain. I used the FX loop and used my Oberheim as an extra filter but may look at some kind of booster.