Water profile and associated off flavor?

I did not want to ask this until I had ruled everything out I could. Here is the problem quickly: I have about 15 AG brews under my belt. I brew on a brutus system with stable mash temps and a single batch sparge. Crush grains with a BC at the factory setting. Ferment in a basement that is around 64-68 year round. Sanitize WELL with Starsan. I have now gotten a Solvent like off flavor on the last 4 brews. They are not green as the last Amber Ale has been in the bottle 8 weeks. I originally thought chlorine so I used Campden tablets overnight. No signs of infection either. Looking at my water chem I now am wondering about tannin extraction during sparge due to Alkaline water. Alkalinity is high but using Palmers PH Nom as well the ez water Calc I have tried to stay in the SRM guidelines. Beer is not terrible but has the flavor. You can actually aerate in the glass and smell it clearly! I have NOT adjusted any salts as of yet.

Any help is appreciated and sorry for the long post.

Mash Water / Total water (ppm):
Ca: 97 / 97
Mg: 40 / 40
Na: 13 / 13
Cl: 18 / 18
SO4: 205 / 205
CaCO3: 257 / 257

RA (mash only): 164 (19 to 23 SRM)
Cl to SO4 (total water): 0.09 (Very Bitter)

Magnesium is high out of range and the CL:SO4 ratio is extremely low. If these are all hoppy beer styles, you could be OK but I'd expect a harsh bitterness, perhaps even metallic aroma and taste from a combo of high SO4, low Cl and high Mg. Certainly that RA is really looking for a Brown beer, anything copper to pale is going to have a pH that is too basic.

I'd start with a 25% dilution with distilled, but if I had your water I'd invest in a $120ish RO system.

Thanks Bobby. No metal flavor just the solvent like. I planned to do a RO dilution on my next batch. I don't want to start a war but what about a dilution, and adding 5.2 to my mash/sparge. Next beer is a Bells clone so the SO4 to Cl would not be a huge issue. The RA will be though? Funny thing is I am in the burbs of Milwaukee so I can get Lake Michigan water which has an overall better profile. Just sucks to go to my brothers house to hall ten gallons of water.